feat(flow): add interactive AI puppet to FlowScreen

- Added puppet component modules: PuppetView, FlowPuppetSlot, and type definitions

- The puppet supports actions such as idle/smile/jump/shake/think, with a default smile.

- FlowScreen integrates puppet slots; it automatically uses the "think" function when sending messages and allows for interactive actions like Smile/Jump/Shake.

- The code is independent of the existing chat logic and does not affect existing functionality.

App.tsx

@@ -4,8 +4,10 @@
  * Main application component with authentication routing.
  * Shows loading screen while restoring auth state.
  */
+import './src/polyfills';
 
 import React from 'react';
+import { Buffer } from 'buffer';
 import { StatusBar } from 'expo-status-bar';
 import { NavigationContainer } from '@react-navigation/native';
 import { GestureHandlerRootView } from 'react-native-gesture-handler';
@@ -15,6 +17,10 @@ import AuthNavigator from './src/navigation/AuthNavigator';
 import { AuthProvider, useAuth } from './src/context/AuthContext';
 import { colors } from './src/theme/colors';
 
+if (typeof globalThis !== 'undefined' && !globalThis.Buffer) {
+  globalThis.Buffer = Buffer;
+}
+
 /**
  * Loading screen shown while restoring auth state
  */

app.json

@@ -19,14 +19,10 @@
       "bundleIdentifier": "com.sentinel.app"
     },
     "android": {
-      "adaptiveIcon": {
-        "foregroundImage": "./assets/adaptive-icon.png",
-        "backgroundColor": "#459E9E"
-      },
       "package": "com.sentinel.app"
     },
     "web": {
-      "favicon": "./assets/favicon.png",
+      "favicon": "./assets/icon.png",
       "bundler": "metro"
     }
   }

metro.config.js

@@ -0,0 +1,15 @@
+const { getDefaultConfig } = require('expo/metro-config');
+const path = require('path');
+
+const config = getDefaultConfig(__dirname);
+
+config.resolver.extraNodeModules = {
+    ...config.resolver.extraNodeModules,
+    crypto: path.resolve(__dirname, 'src/utils/crypto_polyfill.ts'),
+    stream: require.resolve('readable-stream'),
+    vm: require.resolve('vm-browserify'),
+    async_hooks: path.resolve(__dirname, 'src/utils/async_hooks_mock.ts'),
+    'node:async_hooks': path.resolve(__dirname, 'src/utils/async_hooks_mock.ts'),
+};
+
+module.exports = config;

package.json

@@ -11,13 +11,20 @@
   "dependencies": {
     "@expo/metro-runtime": "~4.0.1",
     "@expo/vector-icons": "~14.0.4",
+    "@langchain/core": "^1.1.18",
+    "@langchain/langgraph": "^1.1.3",
+    "@noble/ciphers": "^1.3.0",
+    "@noble/hashes": "^1.8.0",
     "@react-native-async-storage/async-storage": "^2.2.0",
     "@react-navigation/bottom-tabs": "^6.6.1",
     "@react-navigation/native": "^6.1.18",
     "@react-navigation/native-stack": "^6.11.0",
+    "bip39": "^3.1.0",
+    "buffer": "^6.0.3",
     "expo": "~52.0.0",
     "expo-asset": "~11.0.5",
     "expo-constants": "~17.0.8",
+    "expo-crypto": "~14.0.2",
     "expo-font": "~13.0.4",
     "expo-haptics": "~14.0.0",
     "expo-image-picker": "^17.0.10",
@@ -27,11 +34,14 @@
     "react-dom": "18.3.1",
     "react-native": "^0.76.9",
     "react-native-gesture-handler": "~2.20.2",
-    "react-native-view-shot": "^3.8.0",
     "react-native-reanimated": "~3.16.1",
     "react-native-safe-area-context": "4.12.0",
     "react-native-screens": "~4.4.0",
-    "react-native-web": "~0.19.13"
+    "react-native-svg": "^15.15.2",
+    "react-native-view-shot": "^3.8.0",
+    "react-native-web": "~0.19.13",
+    "readable-stream": "^4.7.0",
+    "vm-browserify": "^1.1.2"
   },
   "devDependencies": {
     "@babel/core": "^7.25.2",

src/components/common/BiometricModal.tsx

@@ -62,20 +62,18 @@ export default function BiometricModal({
       Animated.sequence([
         Animated.timing(scanAnimation, {
           toValue: 1,
-          duration: 800,
+          duration: 400,
           useNativeDriver: true,
         }),
         Animated.timing(scanAnimation, {
           toValue: 0,
-          duration: 800,
+          duration: 400,
           useNativeDriver: true,
         }),
       ]),
-      { iterations: 2 }
+      { iterations: 1 }
     ).start(() => {
-      setTimeout(() => {
+      onSuccess();
-        onSuccess();
-      }, 300);
     });
   };
 

src/components/puppet/FlowPuppetSlot.tsx

@@ -0,0 +1,85 @@
+/**
+ * FlowPuppetSlot - Slot for FlowScreen to show interactive AI puppet.
+ * Composes PuppetView and optional action buttons; does not depend on FlowScreen logic.
+ */
+
+import React, { useState, useCallback } from 'react';
+import { View, Text, StyleSheet, TouchableOpacity } from 'react-native';
+import { PuppetView } from './PuppetView';
+import type { FlowPuppetSlotProps, PuppetAction } from './types';
+import { colors } from '../../theme/colors';
+import { borderRadius, spacing } from '../../theme/colors';
+
+const ACTIONS: PuppetAction[] = ['smile', 'jump', 'shake'];
+
+export function FlowPuppetSlot({
+  currentAction,
+  isTalking,
+  onAction,
+  showActionButtons = true,
+}: FlowPuppetSlotProps) {
+  const [localAction, setLocalAction] = useState<PuppetAction>(currentAction);
+
+  const effectiveAction = currentAction !== 'idle' ? currentAction : localAction;
+
+  const handleAction = useCallback(
+    (action: PuppetAction) => {
+      setLocalAction(action);
+      onAction?.(action);
+      if (['smile', 'wave', 'nod', 'shake', 'jump'].includes(action)) {
+        setTimeout(() => {
+          setLocalAction((prev) => (prev === action ? 'idle' : prev));
+          onAction?.('idle');
+        }, 2600);
+      }
+    },
+    [onAction]
+  );
+
+  return (
+    <View style={styles.wrapper}>
+      <PuppetView action={effectiveAction} isTalking={isTalking} />
+      {showActionButtons && (
+        <View style={styles.actions}>
+          {ACTIONS.map((act) => (
+            <TouchableOpacity
+              key={act}
+              style={styles.actionBtn}
+              onPress={() => handleAction(act)}
+              activeOpacity={0.8}
+            >
+              <Text style={styles.actionLabel}>{act}</Text>
+            </TouchableOpacity>
+          ))}
+        </View>
+      )}
+    </View>
+  );
+}
+
+const styles = StyleSheet.create({
+  wrapper: {
+    alignItems: 'center',
+    justifyContent: 'center',
+    paddingVertical: spacing.lg,
+  },
+  actions: {
+    flexDirection: 'row',
+    marginTop: spacing.lg,
+    gap: spacing.sm,
+  },
+  actionBtn: {
+    paddingHorizontal: spacing.md,
+    paddingVertical: spacing.sm,
+    borderRadius: borderRadius.lg,
+    backgroundColor: colors.flow.cardBackground,
+    borderWidth: 1,
+    borderColor: colors.flow.cardBorder,
+  },
+  actionLabel: {
+    fontSize: 12,
+    fontWeight: '600',
+    color: colors.flow.primary,
+    textTransform: 'capitalize',
+  },
+});

src/components/puppet/PuppetView.tsx

@@ -0,0 +1,340 @@
+/**
+ * PuppetView - Interactive blue spirit avatar (React Native).
+ * Port of airi---interactive-ai-puppet Puppet with same actions:
+ * idle, wave, nod, shake, jump, think; mouth reflects isTalking.
+ * Code isolated so FlowScreen stays unchanged except composition.
+ */
+
+import React, { useEffect, useRef } from 'react';
+import { View, StyleSheet, Animated, Easing } from 'react-native';
+import { PuppetViewProps } from './types';
+
+const PUPPET_SIZE = 160;
+
+export function PuppetView({ action, isTalking }: PuppetViewProps) {
+  const floatAnim = useRef(new Animated.Value(0)).current;
+  const bounceAnim = useRef(new Animated.Value(0)).current;
+  const shakeAnim = useRef(new Animated.Value(0)).current;
+  const thinkScale = useRef(new Animated.Value(1)).current;
+  const thinkOpacity = useRef(new Animated.Value(1)).current;
+  const smileScale = useRef(new Animated.Value(1)).current;
+
+  // Idle: gentle float
+  useEffect(() => {
+    if (action !== 'idle') return;
+    const loop = Animated.loop(
+      Animated.sequence([
+        Animated.timing(floatAnim, {
+          toValue: 1,
+          duration: 2000,
+          useNativeDriver: true,
+          easing: Easing.inOut(Easing.ease),
+        }),
+        Animated.timing(floatAnim, {
+          toValue: 0,
+          duration: 2000,
+          useNativeDriver: true,
+          easing: Easing.inOut(Easing.ease),
+        }),
+      ])
+    );
+    loop.start();
+    return () => loop.stop();
+  }, [action, floatAnim]);
+
+  // Smile: exaggerated smile scale pulse
+  useEffect(() => {
+    if (action !== 'smile') {
+      smileScale.setValue(1);
+      return;
+    }
+    const loop = Animated.loop(
+      Animated.sequence([
+        Animated.timing(smileScale, {
+          toValue: 1.12,
+          duration: 400,
+          useNativeDriver: true,
+          easing: Easing.out(Easing.ease),
+        }),
+        Animated.timing(smileScale, {
+          toValue: 1,
+          duration: 400,
+          useNativeDriver: true,
+          easing: Easing.in(Easing.ease),
+        }),
+      ]),
+      { iterations: 3 }
+    );
+    loop.start();
+    return () => loop.stop();
+  }, [action, smileScale]);
+
+  // Wave / Jump: bounce
+  useEffect(() => {
+    if (action !== 'wave' && action !== 'jump') return;
+    const loop = Animated.loop(
+      Animated.sequence([
+        Animated.timing(bounceAnim, {
+          toValue: 1,
+          duration: 400,
+          useNativeDriver: true,
+          easing: Easing.out(Easing.ease),
+        }),
+        Animated.timing(bounceAnim, {
+          toValue: 0,
+          duration: 400,
+          useNativeDriver: true,
+          easing: Easing.in(Easing.ease),
+        }),
+      ])
+    );
+    loop.start();
+    return () => loop.stop();
+  }, [action, bounceAnim]);
+
+  // Shake: wiggle
+  useEffect(() => {
+    if (action !== 'shake') return;
+    const loop = Animated.loop(
+      Animated.sequence([
+        Animated.timing(shakeAnim, {
+          toValue: 1,
+          duration: 150,
+          useNativeDriver: true,
+        }),
+        Animated.timing(shakeAnim, {
+          toValue: 0,
+          duration: 150,
+          useNativeDriver: true,
+        }),
+      ])
+    );
+    loop.start();
+    return () => loop.stop();
+  }, [action, shakeAnim]);
+
+  // Think: scale + opacity pulse
+  useEffect(() => {
+    if (action !== 'think') {
+      thinkScale.setValue(1);
+      thinkOpacity.setValue(1);
+      return;
+    }
+    const loop = Animated.loop(
+      Animated.sequence([
+        Animated.parallel([
+          Animated.timing(thinkScale, {
+            toValue: 0.92,
+            duration: 600,
+            useNativeDriver: true,
+            easing: Easing.inOut(Easing.ease),
+          }),
+          Animated.timing(thinkOpacity, {
+            toValue: 0.85,
+            duration: 600,
+            useNativeDriver: true,
+          }),
+        ]),
+        Animated.parallel([
+          Animated.timing(thinkScale, {
+            toValue: 1,
+            duration: 600,
+            useNativeDriver: true,
+            easing: Easing.inOut(Easing.ease),
+          }),
+          Animated.timing(thinkOpacity, {
+            toValue: 1,
+            duration: 600,
+            useNativeDriver: true,
+          }),
+        ]),
+      ])
+    );
+    loop.start();
+    return () => loop.stop();
+  }, [action, thinkScale, thinkOpacity]);
+
+  const floatY = floatAnim.interpolate({
+    inputRange: [0, 1],
+    outputRange: [0, -8],
+  });
+  const bounceY = bounceAnim.interpolate({
+    inputRange: [0, 1],
+    outputRange: [0, -20],
+  });
+  const shakeRotate = shakeAnim.interpolate({
+    inputRange: [0, 1],
+    outputRange: ['0deg', '8deg'],
+  });
+
+  const isBounce = action === 'wave' || action === 'jump';
+  const isShake = action === 'shake';
+  const isSmile = action === 'smile';
+
+  const mouthStyle = isTalking
+    ? [styles.mouth, styles.mouthOpen]
+    : isSmile
+      ? [styles.mouth, styles.mouthBigSmile]
+      : [styles.mouth, styles.mouthSmile];
+
+  return (
+    <Animated.View
+      style={[
+        styles.container,
+        action === 'idle' && {
+          transform: [{ translateY: floatY }],
+        },
+        isBounce && {
+          transform: [{ translateY: bounceY }],
+        },
+        isShake && {
+          transform: [{ rotate: shakeRotate }],
+        },
+        action === 'think' && {
+          transform: [{ scale: thinkScale }],
+          opacity: thinkOpacity,
+        },
+        isSmile && {
+          transform: [{ scale: smileScale }],
+        },
+      ]}
+    >
+      {/* Aura glow */}
+      <View style={styles.aura} />
+      {/* Body (droplet-like rounded rect) */}
+      <View style={styles.body}>
+        {/* Gloss */}
+        <View style={styles.gloss} />
+        {/* Cheeks */}
+        <View style={[styles.cheek, styles.cheekLeft]} />
+        <View style={[styles.cheek, styles.cheekRight]} />
+        {/* Eyes */}
+        <View style={styles.eyes}>
+          <View style={[styles.eye, styles.eyeLeft]}>
+            <View style={styles.eyeSparkle} />
+          </View>
+          <View style={[styles.eye, styles.eyeRight]}>
+            <View style={styles.eyeSparkle} />
+          </View>
+        </View>
+        {/* Mouth - default smile; open when talking; big smile when smile action */}
+        <View style={mouthStyle} />
+      </View>
+    </Animated.View>
+  );
+}
+
+const BODY_SIZE = PUPPET_SIZE * 0.9;
+const EYE_SIZE = 10;
+const EYE_OFFSET_X = 18;
+const EYE_OFFSET_Y = -8;
+
+const styles = StyleSheet.create({
+  container: {
+    width: PUPPET_SIZE,
+    height: PUPPET_SIZE,
+    alignItems: 'center',
+    justifyContent: 'center',
+  },
+  aura: {
+    position: 'absolute',
+    width: PUPPET_SIZE + 40,
+    height: PUPPET_SIZE + 40,
+    borderRadius: (PUPPET_SIZE + 40) / 2,
+    backgroundColor: 'rgba(14, 165, 233, 0.15)',
+  },
+  body: {
+    width: BODY_SIZE,
+    height: BODY_SIZE,
+    borderRadius: BODY_SIZE / 2,
+    backgroundColor: '#0ea5e9',
+    alignItems: 'center',
+    justifyContent: 'center',
+    borderWidth: 0,
+    overflow: 'hidden',
+    shadowColor: '#0c4a6e',
+    shadowOffset: { width: 0, height: 8 },
+    shadowOpacity: 0.35,
+    shadowRadius: 12,
+    elevation: 8,
+  },
+  gloss: {
+    position: 'absolute',
+    top: BODY_SIZE * 0.12,
+    left: BODY_SIZE * 0.2,
+    right: BODY_SIZE * 0.2,
+    height: 4,
+    borderRadius: 2,
+    backgroundColor: 'rgba(255,255,255,0.35)',
+  },
+  cheek: {
+    position: 'absolute',
+    width: 14,
+    height: 14,
+    borderRadius: 7,
+    backgroundColor: 'rgba(59, 130, 246, 0.35)',
+  },
+  cheekLeft: {
+    left: BODY_SIZE * 0.15,
+    top: BODY_SIZE * 0.42,
+  },
+  cheekRight: {
+    right: BODY_SIZE * 0.15,
+    top: BODY_SIZE * 0.42,
+  },
+  eyes: {
+    flexDirection: 'row',
+    alignItems: 'center',
+    justifyContent: 'center',
+    position: 'absolute',
+    top: BODY_SIZE * 0.34,
+  },
+  eye: {
+    width: EYE_SIZE,
+    height: EYE_SIZE,
+    borderRadius: EYE_SIZE / 2,
+    backgroundColor: '#0c4a6e',
+    alignItems: 'center',
+    justifyContent: 'center',
+  },
+  eyeLeft: { marginRight: EYE_OFFSET_X },
+  eyeRight: { marginLeft: EYE_OFFSET_X },
+  eyeSparkle: {
+    width: 3,
+    height: 3,
+    borderRadius: 1.5,
+    backgroundColor: '#fff',
+    position: 'absolute',
+    top: 1,
+    left: 2,
+  },
+  mouth: {
+    position: 'absolute',
+    top: BODY_SIZE * 0.52,
+    backgroundColor: '#0c4a6e',
+  },
+  mouthSmile: {
+    width: 22,
+    height: 6,
+    borderBottomLeftRadius: 11,
+    borderBottomRightRadius: 11,
+    borderTopLeftRadius: 0,
+    borderTopRightRadius: 0,
+  },
+  mouthOpen: {
+    width: 18,
+    height: 6,
+    top: BODY_SIZE * 0.51,
+    borderRadius: 3,
+    backgroundColor: 'rgba(12, 74, 110, 0.9)',
+  },
+  mouthBigSmile: {
+    width: 32,
+    height: 10,
+    top: BODY_SIZE * 0.51,
+    borderBottomLeftRadius: 16,
+    borderBottomRightRadius: 16,
+    borderTopLeftRadius: 0,
+    borderTopRightRadius: 0,
+  },
+});

src/components/puppet/index.ts

@@ -0,0 +1,3 @@
+export { PuppetView } from './PuppetView';
+export { FlowPuppetSlot } from './FlowPuppetSlot';
+export type { PuppetAction, PuppetState, PuppetViewProps, FlowPuppetSlotProps } from './types';

src/components/puppet/types.ts

@@ -0,0 +1,28 @@
+/**
+ * Puppet types - compatible with airi interactive AI puppet semantics.
+ * Used for FlowScreen multimodal avatar (action + talking state).
+ */
+
+export type PuppetAction = 'idle' | 'wave' | 'nod' | 'shake' | 'jump' | 'think' | 'talk' | 'smile';
+
+export interface PuppetState {
+  currentAction: PuppetAction;
+  isTalking: boolean;
+  isThinking: boolean;
+}
+
+export interface PuppetViewProps {
+  action: PuppetAction;
+  isTalking: boolean;
+}
+
+export interface FlowPuppetSlotProps {
+  /** Current action (idle, wave, nod, shake, jump, think). */
+  currentAction: PuppetAction;
+  /** True when AI is "speaking" (e.g. streaming or responding). */
+  isTalking: boolean;
+  /** Optional: allow parent to set action (e.g. from AI tool call). */
+  onAction?: (action: PuppetAction) => void;
+  /** Show quick action buttons (wave, jump, shake) for interactivity. */
+  showActionButtons?: boolean;
+}

src/config/index.ts

@@ -51,11 +51,13 @@ export const API_ENDPOINTS = {
     CREATE: '/assets/create',
     CLAIM: '/assets/claim',
     ASSIGN: '/assets/assign',
+    DELETE: '/assets/delete',
   },
 
   // AI Services
   AI: {
     PROXY: '/ai/proxy',
+    GET_ROLES: '/get_ai_roles',
   },
 
   // Admin Operations
@@ -64,6 +66,48 @@ export const API_ENDPOINTS = {
   },
 } as const;
 
+// =============================================================================
+// Vault storage (user-isolated, multi-account)
+// =============================================================================
+// - AsyncStorage keys for vault state (S0 share, initialized flag, mnemonic part backup).
+// - User-scoped: each account has its own keys so vault/mnemonic state is isolated.
+// - Store: use getVaultStorageKeys(userId) and write to INITIALIZED / SHARE_DEVICE / MNEMONIC_PART_LOCAL.
+// - Clear: use same keys in multiRemove (e.g. MeScreen Reset Vault State).
+// - Multi-account: same device, multiple users → each has independent vault (no cross-user leakage).
+
+const VAULT_KEY_PREFIX = 'sentinel_vault';
+
+/** Base key names (for reference). Prefer getVaultStorageKeys(userId) for all reads/writes. */
+export const VAULT_STORAGE_KEYS = {
+  INITIALIZED: 'sentinel_vault_initialized',
+  SHARE_DEVICE: 'sentinel_vault_s0',
+  MNEMONIC_PART_LOCAL: 'sentinel_mnemonic_part_local',
+} as const;
+
+/**
+ * Returns vault storage keys for the given user (user isolation).
+ * - Use for: reading/writing S0, mnemonic part backup, clearing on Reset Vault State.
+ * - userId null → guest namespace (_guest). userId set → per-user namespace (_u{userId}).
+ */
+export function getVaultStorageKeys(userId: number | string | null): {
+  INITIALIZED: string;
+  SHARE_DEVICE: string;
+  MNEMONIC_PART_LOCAL: string;
+  AES_KEY: string;
+  SHARE_SERVER: string;
+  SHARE_HEIR: string;
+} {
+  const suffix = userId != null ? `_u${userId}` : '_guest';
+  return {
+    INITIALIZED: `${VAULT_KEY_PREFIX}_initialized${suffix}`,
+    SHARE_DEVICE: `${VAULT_KEY_PREFIX}_s0${suffix}`,
+    MNEMONIC_PART_LOCAL: `sentinel_mnemonic_part_local${suffix}`,
+    AES_KEY: `sentinel_aes_key${suffix}`,
+    SHARE_SERVER: `sentinel_share_server${suffix}`,
+    SHARE_HEIR: `sentinel_share_heir${suffix}`,
+  };
+}
+
 // =============================================================================
 // Helper Functions
 // =============================================================================
@@ -112,6 +156,7 @@ export const MOCK_CONFIG = {
   USER: {
     id: 999,
     username: 'MockCaptain',
+    email: 'captain@sentinel.local',
     public_key: 'mock_public_key',
     is_admin: true,
     guale: false,
@@ -137,6 +182,44 @@ export const AI_CONFIG = {
    * Mock response delay in milliseconds (for NO_BACKEND_MODE)
    */
   MOCK_RESPONSE_DELAY: 500,
+
+  /**
+   * AI Roles configuration
+   */
+  ROLES: [
+    {
+      id: 'reflective',
+      name: 'Reflective Assistant',
+      description: 'Helps you dive deep into your thoughts and feelings through meaningful reflection.',
+      systemPrompt: 'You are a helpful journal assistant. Help the user reflect on their thoughts and feelings.',
+      icon: 'journal-outline',
+      iconFamily: 'Ionicons',
+    },
+    {
+      id: 'creative',
+      name: 'Creative Spark',
+      description: 'A partner for brainstorming, creative writing, and exploring new ideas.',
+      systemPrompt: 'You are a creative brainstorming partner. Help the user explore new ideas, write stories, or look at things from a fresh perspective.',
+      icon: 'bulb-outline',
+      iconFamily: 'Ionicons',
+    },
+    {
+      id: 'planner',
+      name: 'Action Planner',
+      description: 'Focused on turning thoughts into actionable plans and organized goals.',
+      systemPrompt: 'You are a productivity coach. Help the user break down their thoughts into actionable steps and clear goals.',
+      icon: 'list-outline',
+      iconFamily: 'Ionicons',
+    },
+    {
+      id: 'empathetic',
+      name: 'Empathetic Guide',
+      description: 'Provides a safe, non-judgmental space for emotional support and empathy.',
+      systemPrompt: 'You are a supportive and empathetic friend. Listen to the user\'s concerns and provide emotional support without judgment.',
+      icon: 'heart-outline',
+      iconFamily: 'Ionicons',
+    },
+  ],
 } as const;
 
 // =============================================================================

src/context/AuthContext.tsx

@@ -7,8 +7,10 @@
 
 import React, { createContext, useContext, useState, useEffect, ReactNode } from 'react';
 import AsyncStorage from '@react-native-async-storage/async-storage';
-import { User, LoginRequest, RegisterRequest } from '../types';
+import { User, LoginRequest, RegisterRequest, AIRole } from '../types';
 import { authService } from '../services/auth.service';
+import { aiService } from '../services/ai.service';
+import { storageService } from '../services/storage.service';
 
 // =============================================================================
 // Type Definitions
@@ -17,11 +19,13 @@ import { authService } from '../services/auth.service';
 interface AuthContextType {
   user: User | null;
   token: string | null;
+  aiRoles: AIRole[];
   isLoading: boolean;
   isInitializing: boolean;
   signIn: (credentials: LoginRequest) => Promise<void>;
   signUp: (data: RegisterRequest) => Promise<void>;
   signOut: () => void;
+  refreshAIRoles: () => Promise<void>;
 }
 
 // Storage keys
@@ -43,6 +47,7 @@ const AuthContext = createContext<AuthContextType | undefined>(undefined);
 export function AuthProvider({ children }: { children: ReactNode }) {
   const [user, setUser] = useState<User | null>(null);
   const [token, setToken] = useState<string | null>(null);
+  const [aiRoles, setAIRoles] = useState<AIRole[]>([]);
   const [isLoading, setIsLoading] = useState(false);
   const [isInitializing, setIsInitializing] = useState(true);
 
@@ -65,6 +70,8 @@ export function AuthProvider({ children }: { children: ReactNode }) {
         setToken(storedToken);
         setUser(JSON.parse(storedUser));
         console.log('[Auth] Restored session for user:', JSON.parse(storedUser).username);
+        // Fetch AI roles after restoring session
+        fetchAIRoles(storedToken);
       }
     } catch (error) {
       console.error('[Auth] Failed to load stored auth:', error);
@@ -73,6 +80,29 @@ export function AuthProvider({ children }: { children: ReactNode }) {
     }
   };
 
+  /**
+   * Fetch AI roles from API
+   */
+  const fetchAIRoles = async (authToken: string) => {
+    console.log('[Auth] Fetching AI roles with token:', authToken ? `${authToken.substring(0, 10)}...` : 'MISSING');
+    try {
+      const roles = await aiService.getAIRoles(authToken);
+      setAIRoles(roles);
+      console.log('[Auth] AI roles fetched successfully:', roles.length);
+    } catch (error) {
+      console.error('[Auth] Failed to fetch AI roles:', error);
+    }
+  };
+
+  /**
+   * Manual refresh of AI roles
+   */
+  const refreshAIRoles = async () => {
+    if (token) {
+      await fetchAIRoles(token);
+    }
+  };
+
   /**
    * Save authentication to AsyncStorage
    */
@@ -113,6 +143,8 @@ export function AuthProvider({ children }: { children: ReactNode }) {
       setToken(response.access_token);
       setUser(response.user);
       await saveAuth(response.access_token, response.user);
+      // Fetch AI roles immediately after login
+      await fetchAIRoles(response.access_token);
     } catch (error) {
       throw error;
     } finally {
@@ -137,12 +169,16 @@ export function AuthProvider({ children }: { children: ReactNode }) {
   };
 
   /**
-   * Sign out and clear stored auth
+   * Sign out and clear stored auth and session data
    */
   const signOut = () => {
     setUser(null);
     setToken(null);
+    setAIRoles([]);
     clearAuth();
+
+
+    //storageService.clearAllData();
   };
 
   return (
@@ -150,11 +186,13 @@ export function AuthProvider({ children }: { children: ReactNode }) {
       value={{
         user,
         token,
+        aiRoles,
         isLoading,
         isInitializing,
         signIn,
         signUp,
-        signOut 
+        signOut,
+        refreshAIRoles
       }}
     >
       {children}

src/hooks/index.ts

@@ -0,0 +1,6 @@
+/**
+ * React hooks for Sentinel
+ */
+
+export { useVaultAssets } from './useVaultAssets';
+export type { CreateAssetResult, UseVaultAssetsReturn } from './useVaultAssets';

src/hooks/useVaultAssets.ts

@@ -0,0 +1,278 @@
+/**
+ * useVaultAssets: Encapsulates /assets/get and /assets/create for VaultScreen.
+ * - Fetches assets when vault is unlocked and token exists.
+ * - Exposes createAsset with 401/network error handling and list refresh on success.
+ */
+
+import { useState, useEffect, useCallback } from 'react';
+import * as bip39 from 'bip39';
+import AsyncStorage from '@react-native-async-storage/async-storage';
+import { useAuth } from '../context/AuthContext';
+import { assetsService } from '../services/assets.service';
+import { getVaultStorageKeys, DEBUG_MODE } from '../config';
+import { SentinelVault } from '../utils/crypto_core';
+import { storageService } from '../services/storage.service';
+import {
+  initialVaultAssets,
+  mapApiAssetsToVaultAssets,
+  type ApiAsset,
+} from '../utils/vaultAssets';
+import type { VaultAsset } from '../types';
+
+// -----------------------------------------------------------------------------
+// Types
+// -----------------------------------------------------------------------------
+
+export interface CreateAssetResult {
+  success: boolean;
+  isUnauthorized?: boolean;
+  error?: string;
+}
+
+export interface UseVaultAssetsReturn {
+  /** Current list (mock until API succeeds) */
+  assets: VaultAsset[];
+  /** Replace list (e.g. after external refresh) */
+  setAssets: React.Dispatch<React.SetStateAction<VaultAsset[]>>;
+  /** Refetch from GET /assets/get */
+  refreshAssets: () => Promise<void>;
+  /** Create asset via POST /assets/create; on success refreshes list */
+  createAsset: (params: { title: string; content: string }) => Promise<CreateAssetResult>;
+  /** Delete asset via POST /assets/delete; on success refreshes list */
+  deleteAsset: (assetId: number) => Promise<CreateAssetResult>;
+  /** Assign asset to heir via POST /assets/assign */
+  assignAsset: (assetId: number, heirEmail: string) => Promise<CreateAssetResult>;
+  /** True while create request is in flight */
+  isSealing: boolean;
+  /** Error message from last create failure (non-401) */
+  createError: string | null;
+  /** Clear createError */
+  clearCreateError: () => void;
+}
+
+// -----------------------------------------------------------------------------
+// Hook
+// -----------------------------------------------------------------------------
+
+/**
+ * Vault assets list + create. Fetches on unlock when token exists; keeps mock on error.
+ */
+export function useVaultAssets(isUnlocked: boolean): UseVaultAssetsReturn {
+  const { user, token, signOut } = useAuth();
+  const [assets, setAssets] = useState<VaultAsset[]>(initialVaultAssets);
+  const [isSealing, setIsSealing] = useState(false);
+  const [createError, setCreateError] = useState<string | null>(null);
+
+  const refreshAssets = useCallback(async () => {
+    if (!token) return;
+    try {
+      const list = await assetsService.getMyAssets(token);
+      if (Array.isArray(list)) {
+        setAssets(mapApiAssetsToVaultAssets(list as ApiAsset[]));
+      }
+    } catch (err: unknown) {
+      const rawMessage = err instanceof Error ? err.message : String(err ?? '');
+      if (/Could not validate credentials/i.test(rawMessage)) {
+        signOut();
+      }
+      // Keep current assets (mock or previous fetch)
+    }
+  }, [token, signOut]);
+
+  // Fetch list when unlocked and token exists
+  useEffect(() => {
+    if (!isUnlocked || !token) return;
+    let cancelled = false;
+    assetsService
+      .getMyAssets(token)
+      .then((list) => {
+        if (!cancelled && Array.isArray(list)) {
+          setAssets(mapApiAssetsToVaultAssets(list as ApiAsset[]));
+        }
+      })
+      .catch((err) => {
+        if (!cancelled) {
+          const rawMessage = err instanceof Error ? err.message : String(err ?? '');
+          if (/Could not validate credentials/i.test(rawMessage)) {
+            signOut();
+          }
+        }
+        // Keep initial (mock) assets
+      });
+    return () => {
+      cancelled = true;
+    };
+  }, [isUnlocked, token]);
+
+  const createAsset = useCallback(
+    async ({
+      title,
+      content,
+    }: {
+      title: string;
+      content: string;
+    }): Promise<CreateAssetResult> => {
+      if (!token) {
+        return { success: false, error: 'Not logged in.' };
+      }
+      setIsSealing(true);
+      setCreateError(null);
+      try {
+        const vaultKeys = getVaultStorageKeys(user?.id ?? null);
+        const [s1Str, aesKeyHex, s0Str, s2Str] = await Promise.all([
+          AsyncStorage.getItem(vaultKeys.SHARE_SERVER),
+          AsyncStorage.getItem(vaultKeys.AES_KEY),
+          AsyncStorage.getItem(vaultKeys.SHARE_DEVICE),
+          AsyncStorage.getItem(vaultKeys.SHARE_HEIR),
+        ]);
+
+        if (!s1Str || !aesKeyHex) {
+          throw new Error('Vault keys missing. Please re-unlock your vault.');
+        }
+
+        const vault = new SentinelVault();
+        const aesKey = Buffer.from(aesKeyHex, 'hex');
+        const encryptedBuffer = vault.encryptData(aesKey, content.trim());
+        const content_inner_encrypted = encryptedBuffer.toString('hex');
+
+        if (DEBUG_MODE) {
+          console.log('[DEBUG] Crypto Data during Asset Creation:');
+          console.log('  s0 (Device):', s0Str);
+          console.log('  s1 (Server):', s1Str);
+          console.log('  s2 (Heir):  ', s2Str);
+          console.log('  AES Key:    ', aesKeyHex);
+          console.log('  Encrypted:  ', content_inner_encrypted);
+        }
+
+        const createdAsset = await assetsService.createAsset(
+          {
+            title: title.trim(),
+            private_key_shard: s1Str,
+            content_inner_encrypted,
+          },
+          token
+        );
+
+        // Backup plaintext content locally
+        if (createdAsset && createdAsset.id && user?.id) {
+          await storageService.saveAssetBackup(createdAsset.id, content, user.id);
+        }
+        await refreshAssets();
+        return { success: true };
+      } catch (err: unknown) {
+        const status =
+          err && typeof err === 'object' && 'status' in err
+            ? (err as { status?: number }).status
+            : undefined;
+        const rawMessage =
+          err instanceof Error ? err.message : String(err ?? 'Failed to create.');
+        const isUnauthorized =
+          status === 401 || /401|Unauthorized/i.test(rawMessage);
+
+        if (isUnauthorized) {
+          signOut();
+          return { success: false, isUnauthorized: true };
+        }
+
+        const friendlyMessage = /failed to fetch|network error/i.test(rawMessage)
+          ? 'Network error. Please check that the backend is running and reachable (see API_BASE_URL in config).'
+          : rawMessage;
+        setCreateError(friendlyMessage);
+        return { success: false, error: friendlyMessage };
+      } finally {
+        setIsSealing(false);
+      }
+    },
+    [token, user, refreshAssets, signOut]
+  );
+
+  const deleteAsset = useCallback(
+    async (assetId: number): Promise<CreateAssetResult> => {
+      if (!token) {
+        return { success: false, error: 'Not logged in.' };
+      }
+      setIsSealing(true);
+      setCreateError(null);
+      try {
+        await assetsService.deleteAsset(assetId, token);
+        await refreshAssets();
+        return { success: true };
+      } catch (err: unknown) {
+        const status =
+          err && typeof err === 'object' && 'status' in err
+            ? (err as { status?: number }).status
+            : undefined;
+        const rawMessage =
+          err instanceof Error ? err.message : String(err ?? 'Failed to delete.');
+        const isUnauthorized =
+          status === 401 || /401|Unauthorized/i.test(rawMessage);
+
+        if (isUnauthorized) {
+          signOut();
+          return { success: false, isUnauthorized: true };
+        }
+
+        const friendlyMessage = /failed to fetch|network error/i.test(rawMessage)
+          ? 'Network error. Please check that the backend is running and reachable.'
+          : rawMessage;
+        setCreateError(friendlyMessage);
+        return { success: false, error: friendlyMessage };
+      } finally {
+        setIsSealing(false);
+      }
+    },
+    [token, refreshAssets, signOut]
+  );
+
+  const assignAsset = useCallback(
+    async (assetId: number, heirEmail: string): Promise<CreateAssetResult> => {
+      if (!token) {
+        return { success: false, error: 'Not logged in.' };
+      }
+      setIsSealing(true);
+      setCreateError(null);
+      try {
+        await assetsService.assignAsset({ asset_id: assetId, heir_email: heirEmail }, token);
+        await refreshAssets();
+        return { success: true };
+      } catch (err: unknown) {
+        const status =
+          err && typeof err === 'object' && 'status' in err
+            ? (err as { status?: number }).status
+            : undefined;
+        const rawMessage =
+          err instanceof Error ? err.message : String(err ?? 'Failed to assign.');
+        const isUnauthorized =
+          status === 401 || /401|Unauthorized/i.test(rawMessage);
+
+        if (isUnauthorized) {
+          signOut();
+          return { success: false, isUnauthorized: true };
+        }
+
+        const friendlyMessage = /failed to fetch|network error/i.test(rawMessage)
+          ? 'Network error. Please check that the backend is running and reachable.'
+          : rawMessage;
+        setCreateError(friendlyMessage);
+        return { success: false, error: friendlyMessage };
+      } finally {
+        setIsSealing(false);
+      }
+    },
+    [token, signOut]
+  );
+
+  const clearCreateError = useCallback(() => setCreateError(null), []);
+
+  return {
+    assets,
+    setAssets,
+    refreshAssets,
+    createAsset,
+    deleteAsset,
+    assignAsset,
+    isSealing,
+    createError,
+    clearCreateError,
+  };
+}

src/polyfills.ts

@@ -0,0 +1,45 @@
+/**
+ * Polyfills that must run before any other app code (including LangChain/LangGraph).
+ * This file is imported as the very first line in App.tsx so that ReadableStream
+ * and crypto.getRandomValues exist before @langchain/core / uuid are loaded.
+ */
+import 'web-streams-polyfill';
+
+// Ensure globalThis has ReadableStream (main polyfill may not patch in RN/Metro)
+const g = typeof globalThis !== 'undefined' ? globalThis : (typeof global !== 'undefined' ? global : (typeof self !== 'undefined' ? self : {}));
+if (typeof (g as any).ReadableStream === 'undefined') {
+  const ponyfill = require('web-streams-polyfill/dist/ponyfill.js');
+  (g as any).ReadableStream = ponyfill.ReadableStream;
+  (g as any).WritableStream = ponyfill.WritableStream;
+  (g as any).TransformStream = ponyfill.TransformStream;
+}
+
+// Polyfill crypto.getRandomValues for React Native/Expo (required by uuid, LangChain, etc.)
+if (typeof g !== 'undefined') {
+  const cryptoObj = (g as any).crypto;
+  if (!cryptoObj || typeof (cryptoObj.getRandomValues) !== 'function') {
+    try {
+      const ExpoCrypto = require('expo-crypto');
+      const getRandomValues = (array: ArrayBufferView): ArrayBufferView => {
+        ExpoCrypto.getRandomValues(array);
+        return array;
+      };
+      if (!(g as any).crypto) (g as any).crypto = {};
+      (g as any).crypto.getRandomValues = getRandomValues;
+    } catch (e) {
+      console.warn('[polyfills] crypto.getRandomValues polyfill failed:', e);
+    }
+  }
+}
+
+// Polyfill AbortSignal.prototype.throwIfAborted (required by fetch/LangChain in RN; not present in older runtimes)
+const AbortSignalGlobal = (g as any).AbortSignal;
+if (typeof AbortSignalGlobal === 'function' && AbortSignalGlobal.prototype && typeof AbortSignalGlobal.prototype.throwIfAborted !== 'function') {
+  AbortSignalGlobal.prototype.throwIfAborted = function (this: AbortSignal) {
+    if (this.aborted) {
+      const e = new Error('Aborted');
+      e.name = 'AbortError';
+      throw e;
+    }
+  };
+}

src/screens/FlowScreen.tsx

@@ -28,9 +28,20 @@ import {
 import { LinearGradient } from 'expo-linear-gradient';
 import { Ionicons, Feather, FontAwesome5 } from '@expo/vector-icons';
 import * as ImagePicker from 'expo-image-picker';
+import { AIRole } from '../types';
 import { colors, typography, spacing, borderRadius, shadows } from '../theme/colors';
-import { aiService } from '../services/ai.service';
+import { aiService, AIMessage } from '../services/ai.service';
+import { langGraphService } from '../services/langgraph.service';
+import { HumanMessage, AIMessage as LangChainAIMessage, SystemMessage } from "@langchain/core/messages";
+import { assetsService } from '../services/assets.service';
 import { useAuth } from '../context/AuthContext';
+import { AI_CONFIG, getVaultStorageKeys } from '../config';
+import { storageService } from '../services/storage.service';
+import AsyncStorage from '@react-native-async-storage/async-storage';
+import { SentinelVault } from '../utils/crypto_core';
+import { Buffer } from 'buffer';
+import { FlowPuppetSlot } from '../components/puppet';
+import type { PuppetAction } from '../components/puppet';
 
 // =============================================================================
 // Type Definitions
@@ -57,7 +68,7 @@ interface ChatSession {
 // =============================================================================
 
 export default function FlowScreen() {
-  const { token, signOut } = useAuth();
+  const { token, user, signOut, aiRoles, refreshAIRoles } = useAuth();
   const scrollViewRef = useRef<ScrollView>(null);
 
   // Current conversation state
@@ -67,10 +78,30 @@ export default function FlowScreen() {
   const [isRecording, setIsRecording] = useState(false);
   const [selectedImage, setSelectedImage] = useState<string | null>(null);
 
+  // AI Role state - start with null to detect first load
+  const [selectedRole, setSelectedRole] = useState<AIRole | null>(aiRoles[0] || null);
+  const [showRoleModal, setShowRoleModal] = useState(false);
+  const [expandedRoleId, setExpandedRoleId] = useState<string | null>(null);
+
   // History modal state
   const [showHistoryModal, setShowHistoryModal] = useState(false);
   const modalSlideAnim = useRef(new Animated.Value(0)).current;
 
+  // Summary state
+  const [showSummaryConfirmModal, setShowSummaryConfirmModal] = useState(false);
+  const [showSummaryResultModal, setShowSummaryResultModal] = useState(false);
+  const [isSummarizing, setIsSummarizing] = useState(false);
+  const [generatedSummary, setGeneratedSummary] = useState('');
+
+  // Save to Vault state
+  const [showVaultConfirmModal, setShowVaultConfirmModal] = useState(false);
+  const [showSaveResultModal, setShowSaveResultModal] = useState(false);
+  const [saveResult, setSaveResult] = useState<{ success: boolean; message: string }>({ success: true, message: '' });
+  const [isSavingToVault, setIsSavingToVault] = useState(false);
+
+  // AI multimodal puppet (optional; does not affect existing chat logic)
+  const [puppetAction, setPuppetAction] = useState<PuppetAction>('idle');
+
   const [chatHistory, setChatHistory] = useState<ChatSession[]>([
     // Sample history data
     {
@@ -104,14 +135,108 @@ export default function FlowScreen() {
     day: 'numeric'
   });
 
-  // Auto-scroll to bottom when new messages arrive
+  // Load history on mount
   useEffect(() => {
+    const loadHistory = async () => {
+      if (!user) return;
+      try {
+        console.log('[FlowScreen] Loading chat history...');
+        const savedHistory = await storageService.getChatHistory(user.id);
+        if (savedHistory && savedHistory.length > 0) {
+          const formattedHistory = savedHistory.map((session: any) => ({
+            ...session,
+            createdAt: new Date(session.createdAt),
+            updatedAt: new Date(session.updatedAt),
+            messages: session.messages.map((msg: any) => ({
+              ...msg,
+              createdAt: new Date(msg.createdAt)
+            }))
+          }));
+          setChatHistory(formattedHistory);
+          console.log('[FlowScreen] Chat history loaded:', formattedHistory.length, 'sessions');
+        } else {
+          console.log('[FlowScreen] No chat history found');
+        }
+      } catch (error) {
+        console.error('Failed to load history:', error);
+      }
+    };
+    loadHistory();
+  }, [user]);
+
+  // Load messages whenever role changes
+  useEffect(() => {
+    const loadRoleMessages = async () => {
+      if (!user || !selectedRole) return;
+      try {
+        const savedMessages = await storageService.getCurrentChat(selectedRole?.id || '', user.id);
+        if (savedMessages) {
+          const formattedMessages = savedMessages.map((msg: any) => ({
+            ...msg,
+            createdAt: new Date(msg.createdAt)
+          }));
+          setMessages(formattedMessages);
+        } else {
+          setMessages([]);
+        }
+      } catch (error) {
+        if (selectedRole) {
+          console.error(`Failed to load messages for role ${selectedRole?.id}:`, error);
+        }
+        setMessages([]);
+      }
+    };
+
+    loadRoleMessages();
+  }, [selectedRole?.id, user]);
+
+  // Ensure we have a valid selected role from the dynamic list
+  useEffect(() => {
+    if (aiRoles.length > 0) {
+      if (!selectedRole) {
+        // Initial load or first time roles become available
+        setSelectedRole(aiRoles[0]);
+      } else {
+        // If roles refreshed, make sure current selectedRole is still valid or updated
+        const updatedRole = aiRoles.find(r => r.id === selectedRole?.id);
+        if (updatedRole) {
+          setSelectedRole(updatedRole);
+        } else {
+          // Current role no longer exists in dynamic list, fallback to first
+          setSelectedRole(aiRoles[0]);
+        }
+      }
+    } else if (!selectedRole) {
+      // Fallback if no dynamic roles yet
+      setSelectedRole(AI_CONFIG.ROLES[0]);
+    }
+  }, [aiRoles]);
+
+  // Sync puppet action with sending state (think while AI is responding)
+  useEffect(() => {
+    if (isSending) setPuppetAction('think');
+    else setPuppetAction((prev) => (prev === 'think' ? 'idle' : prev));
+  }, [isSending]);
+
+  // Save current messages for the active role when they change
+  useEffect(() => {
+    if (user && selectedRole && messages.length >= 0) { // Save even if empty to allow clearing
+      storageService.saveCurrentChat(selectedRole?.id || '', messages, user.id);
+    }
+
     if (messages.length > 0) {
       setTimeout(() => {
         scrollViewRef.current?.scrollToEnd({ animated: true });
       }, 100);
     }
-  }, [messages]);
+  }, [messages, selectedRole?.id, user]);
+
+  // Save history when it changes
+  useEffect(() => {
+    if (user) {
+      storageService.saveChatHistory(chatHistory, user.id);
+    }
+  }, [chatHistory, user]);
 
   // Modal animation control
   const openHistoryModal = () => {
@@ -142,7 +267,7 @@ export default function FlowScreen() {
    * Handle sending a message to AI
    */
   const handleSendMessage = async () => {
-    if (!newContent.trim() || isSending) return;
+    if (!newContent.trim() || isSending || !selectedRole) return;
 
     // Check authentication
     if (!token) {
@@ -168,8 +293,23 @@ export default function FlowScreen() {
     setMessages(prev => [...prev, userMsg]);
 
     try {
-      // Call AI proxy
+      // 1. Convert current messages history to LangChain format
-      const aiResponse = await aiService.sendMessage(userMessage, token);
+      const history: (HumanMessage | LangChainAIMessage | SystemMessage)[] = messages.map(msg => {
+        if (msg.role === 'user') return new HumanMessage(msg.content);
+        return new LangChainAIMessage(msg.content);
+      });
+
+      // 2. Add system prompt
+      const systemPrompt = new SystemMessage(selectedRole?.systemPrompt || '');
+
+      // 3. Add current new message
+      const currentMsg = new HumanMessage(userMessage);
+
+      // 4. Combine all messages for LangGraph processing
+      const fullMessages = [systemPrompt, ...history, currentMsg];
+
+      // 5. Execute via LangGraph service (handles token limits and context)
+      const aiResponse = await langGraphService.execute(fullMessages, token);
 
       // Add AI response
       const aiMsg: ChatMessage = {
@@ -335,8 +475,11 @@ export default function FlowScreen() {
       setChatHistory(prev => [newSession, ...prev]);
     }
 
-    // Clear current messages
+    // Clear current messages and storage for this role
     setMessages([]);
+    if (user && selectedRole) {
+      storageService.saveCurrentChat(selectedRole?.id || '', [], user.id);
+    }
     closeHistoryModal();
   };
 
@@ -379,6 +522,112 @@ export default function FlowScreen() {
     );
   };
 
+  /**
+   * Handle generating summary for current conversation
+   */
+  const handleGenerateSummary = async () => {
+    if (messages.length === 0) {
+      Alert.alert('No Messages', 'There are no messages to summarize.');
+      return;
+    }
+
+    if (!token) {
+      Alert.alert('Login Required', 'Please login to generate a summary.');
+      return;
+    }
+
+    setShowSummaryConfirmModal(false);
+    setIsSummarizing(true);
+
+    try {
+      // Convert messages to AIMessage format
+      const aiMessages: AIMessage[] = messages.map(msg => ({
+        role: msg.role,
+        content: msg.content,
+      }));
+
+      const summary = await aiService.summarizeChat(aiMessages, token);
+      setGeneratedSummary(summary);
+      setShowSummaryResultModal(true);
+    } catch (error) {
+      console.error('Failed to generate summary:', error);
+      Alert.alert('Error', 'Failed to generate summary. Please try again later.');
+    } finally {
+      setIsSummarizing(false);
+    }
+  };
+
+  /**
+   * Handle saving the generated summary to the vault
+   */
+  const handleSaveToVault = async () => {
+    if (!generatedSummary || isSavingToVault) return;
+
+    if (!token) {
+      Alert.alert('Login Required', 'Please login to save to vault.');
+      return;
+    }
+
+    setShowVaultConfirmModal(false);
+    setIsSavingToVault(true);
+
+    try {
+      // Retrieve vault keys
+      if (!user) {
+        Alert.alert('Error', 'User information not found. Please login again.');
+        return;
+      }
+      const vaultKeys = getVaultStorageKeys(user.id);
+      const shareServer = await AsyncStorage.getItem(vaultKeys.SHARE_SERVER);
+      const aesKeyHex = await AsyncStorage.getItem(vaultKeys.AES_KEY);
+
+      if (!shareServer || !aesKeyHex) {
+        Alert.alert(
+          'Vault Not Initialized',
+          'Your vault is not fully initialized. Please set it up in the Vault tab first.'
+        );
+        return;
+      }
+
+      // Encrypt summary with AES key
+      const vault = new SentinelVault();
+      const aesKey = Buffer.from(aesKeyHex, 'hex');
+      const encryptedSummary = vault.encryptData(aesKey, generatedSummary).toString('hex');
+
+      // Create asset in backend
+      const createdAsset = await assetsService.createAsset({
+        title: `Chat Summary - ${new Date().toLocaleDateString()}`,
+        private_key_shard: shareServer,
+        content_inner_encrypted: encryptedSummary,
+      }, token);
+
+      // Backup plaintext content locally
+      if (createdAsset && createdAsset.id && user?.id) {
+        await storageService.saveAssetBackup(createdAsset.id, generatedSummary, user.id);
+      }
+
+      setSaveResult({ success: true, message: 'Summary encrypted and saved to your vault successfully.' });
+      setShowSaveResultModal(true);
+    } catch (error) {
+      console.error('Failed to save to vault:', error);
+      setSaveResult({ success: false, message: 'Failed to save summary to vault. Please try again.' });
+      setShowSaveResultModal(true);
+    } finally {
+      setIsSavingToVault(false);
+    }
+  };
+
+  /**
+   * Handle closing all summary related modals after successful save or manual close of result
+   */
+  const handleFinishSaveFlow = () => {
+    setShowSaveResultModal(false);
+    if (saveResult.success) {
+      setShowSummaryResultModal(false);
+      setShowVaultConfirmModal(false);
+    }
+  };
+
   // =============================================================================
   // Helper Functions
   // =============================================================================
@@ -451,9 +700,9 @@ export default function FlowScreen() {
       <View style={styles.emptyIcon}>
         <Feather name="feather" size={48} color={colors.nautical.seafoam} />
       </View>
-      <Text style={styles.emptyTitle}>Start a conversation</Text>
+      <Text style={styles.emptyTitle}>Chatting with {selectedRole?.name || 'AI'}</Text>
       <Text style={styles.emptySubtitle}>
-        Ask me anything or share your thoughts
+        {selectedRole?.description || 'Loading AI Assistant...'}
       </Text>
     </View>
   );
@@ -505,6 +754,38 @@ export default function FlowScreen() {
               </View>
             </View>
 
+            {/* Role Header Dropdown */}
+            <TouchableOpacity
+              style={styles.headerRoleButton}
+              onPress={() => setShowRoleModal(true)}
+              activeOpacity={0.7}
+            >
+              {selectedRole && (
+                <Ionicons
+                  name={(selectedRole?.icon || 'help-outline') as any}
+                  size={16}
+                  color={colors.nautical.teal}
+                />
+              )}
+              <Text style={styles.headerRoleText} numberOfLines={1}>
+                {selectedRole?.name || 'Loading...'}
+              </Text>
+              <Ionicons name="chevron-down" size={14} color={colors.flow.textSecondary} />
+            </TouchableOpacity>
+
+            {/* Summary Button */}
+            <TouchableOpacity
+              style={[styles.historyButton, { marginRight: spacing.sm }]}
+              onPress={() => setShowSummaryConfirmModal(true)}
+              disabled={messages.length === 0 || isSummarizing}
+            >
+              <Ionicons
+                name="document-text-outline"
+                size={20}
+                color={messages.length === 0 || isSummarizing ? colors.flow.textSecondary : colors.flow.primary}
+              />
+            </TouchableOpacity>
+
             {/* History Button */}
             <TouchableOpacity
               style={styles.historyButton}
@@ -514,6 +795,14 @@ export default function FlowScreen() {
             </TouchableOpacity>
           </View>
 
+          {/* AI multimodal puppet (optional slot; code in components/puppet) */}
+          <FlowPuppetSlot
+            currentAction={puppetAction}
+            isTalking={isSending}
+            onAction={setPuppetAction}
+            showActionButtons={true}
+          />
+
           {/* Chat Messages */}
           <ScrollView
             ref={scrollViewRef}
@@ -607,7 +896,6 @@ export default function FlowScreen() {
         </SafeAreaView>
       </LinearGradient>
 
-      {/* History Modal - Background appears instantly, content slides up */}
       <Modal
         visible={showHistoryModal}
         animationType="none"
@@ -630,46 +918,335 @@ export default function FlowScreen() {
                   }
                 ]}
               >
-            <View style={styles.modalHandle} />
+                <View style={styles.modalHandle} />
 
-            {/* Modal Header */}
+                {/* Modal Header */}
-            <View style={styles.modalHeader}>
+                <View style={styles.modalHeader}>
-              <Text style={styles.modalTitle}>Chat History</Text>
+                  <Text style={styles.modalTitle}>Chat History</Text>
-              <TouchableOpacity 
+                  <TouchableOpacity
-                style={styles.newChatButton}
+                    style={styles.newChatButton}
-                onPress={handleNewChat}
+                    onPress={handleNewChat}
-              >
+                  >
-                <Ionicons name="add" size={20} color="#fff" />
+                    <Ionicons name="add" size={20} color="#fff" />
-                <Text style={styles.newChatText}>New Chat</Text>
+                    <Text style={styles.newChatText}>New Chat</Text>
-              </TouchableOpacity>
+                  </TouchableOpacity>
-            </View>
-            
-            {/* History List */}
-            <FlatList
-              data={chatHistory}
-              renderItem={renderHistoryItem}
-              keyExtractor={item => item.id}
-              style={styles.historyList}
-              ListEmptyComponent={
-                <View style={styles.historyEmpty}>
-                  <Ionicons name="chatbubbles-outline" size={48} color={colors.flow.textSecondary} />
-                  <Text style={styles.historyEmptyText}>No chat history yet</Text>
                 </View>
-              }
-            />
 
-            {/* Close Button */}
+                {/* History List */}
-            <TouchableOpacity 
+                <FlatList
-              style={styles.closeButton}
+                  data={chatHistory}
-              onPress={closeHistoryModal}
+                  renderItem={renderHistoryItem}
-            >
+                  keyExtractor={item => item.id}
-              <Text style={styles.closeButtonText}>Close</Text>
+                  style={styles.historyList}
-            </TouchableOpacity>
+                  ListEmptyComponent={
+                    <View style={styles.historyEmpty}>
+                      <Ionicons name="chatbubbles-outline" size={48} color={colors.flow.textSecondary} />
+                      <Text style={styles.historyEmptyText}>No chat history yet</Text>
+                    </View>
+                  }
+                />
+
+                {/* Close Button */}
+                <TouchableOpacity
+                  style={styles.closeButton}
+                  onPress={closeHistoryModal}
+                >
+                  <Text style={styles.closeButtonText}>Close</Text>
+                </TouchableOpacity>
               </Animated.View>
             </TouchableWithoutFeedback>
           </View>
         </TouchableWithoutFeedback>
       </Modal>
+
+      {/* Role Selection Modal */}
+      <Modal
+        visible={showRoleModal}
+        animationType="fade"
+        transparent
+        onRequestClose={() => setShowRoleModal(false)}
+      >
+        <TouchableWithoutFeedback onPress={() => setShowRoleModal(false)}>
+          <View style={styles.modalOverlay}>
+            <TouchableWithoutFeedback onPress={(e) => e.stopPropagation()}>
+              <View style={[styles.modalContent, styles.roleModalContent]}>
+                <View style={styles.modalHandle} />
+                <Text style={styles.modalTitle}>Choose AI Assistant</Text>
+
+                <ScrollView style={styles.roleList} showsVerticalScrollIndicator={false}>
+                  {aiRoles.map((role) => (
+                    <View key={role.id} style={styles.roleItemContainer}>
+                      <View
+                        style={[
+                          styles.roleItem,
+                          selectedRole?.id === role.id && styles.roleItemActive
+                        ]}
+                      >
+                        <TouchableOpacity
+                          style={styles.roleSelectionArea}
+                          onPress={() => {
+                            setSelectedRole(role);
+                            setShowRoleModal(false);
+                          }}
+                        >
+                          <View style={[
+                            styles.roleItemIcon,
+                            selectedRole?.id === role.id && styles.roleItemIconActive
+                          ]}>
+                            <Ionicons
+                              name={role.icon as any}
+                              size={20}
+                              color={selectedRole?.id === role.id ? '#fff' : colors.nautical.teal}
+                            />
+                          </View>
+                          <Text style={[
+                            styles.roleItemName,
+                            selectedRole?.id === role.id && styles.roleItemNameActive
+                          ]}>
+                            {role.name}
+                          </Text>
+                        </TouchableOpacity>
+
+                        <TouchableOpacity
+                          style={styles.infoButton}
+                          onPress={() => {
+                            setExpandedRoleId(expandedRoleId === role.id ? null : role.id);
+                          }}
+                        >
+                          <Ionicons
+                            name={expandedRoleId === role.id ? "close-circle-outline" : "information-circle-outline"}
+                            size={24}
+                            color={expandedRoleId === role.id ? colors.nautical.coral : colors.flow.textSecondary}
+                          />
+                        </TouchableOpacity>
+                      </View>
+
+                      {expandedRoleId === role.id && (
+                        <View style={styles.roleDescription}>
+                          <Text style={styles.roleDescriptionText}>{role.description}</Text>
+                        </View>
+                      )}
+                    </View>
+                  ))}
+                </ScrollView>
+
+                <TouchableOpacity
+                  style={styles.closeButton}
+                  onPress={() => setShowRoleModal(false)}
+                >
+                  <Text style={styles.closeButtonText}>Cancel</Text>
+                </TouchableOpacity>
+              </View>
+            </TouchableWithoutFeedback>
+          </View>
+        </TouchableWithoutFeedback>
+      </Modal>
+
+      {/* Summary Confirmation Modal */}
+      <Modal
+        visible={showSummaryConfirmModal}
+        transparent
+        animationType="fade"
+        onRequestClose={() => setShowSummaryConfirmModal(false)}
+      >
+        <TouchableWithoutFeedback onPress={() => setShowSummaryConfirmModal(false)}>
+          <View style={styles.modalOverlay}>
+            <TouchableWithoutFeedback onPress={e => e.stopPropagation()}>
+              <View style={[styles.modalContent, { paddingBottom: spacing.xl }]}>
+                <View style={styles.modalHandle} />
+                <Text style={styles.modalTitle}>Generate Summary</Text>
+                <Text style={[styles.modalSubtitle, { marginVertical: spacing.base }]}>
+                  Would you like to generate a summary for the current conversation?
+                </Text>
+
+                <View style={styles.modalActions}>
+                  <TouchableOpacity
+                    style={[styles.actionButton, styles.cancelButton]}
+                    onPress={() => setShowSummaryConfirmModal(false)}
+                  >
+                    <Text style={styles.cancelButtonText}>No</Text>
+                  </TouchableOpacity>
+                  <TouchableOpacity
+                    style={[styles.actionButton, styles.confirmButton]}
+                    onPress={handleGenerateSummary}
+                  >
+                    <LinearGradient
+                      colors={[colors.nautical.teal, colors.nautical.seafoam]}
+                      style={styles.actionButtonGradient}
+                    >
+                      <Text style={styles.confirmButtonText}>Yes, Generate</Text>
+                    </LinearGradient>
+                  </TouchableOpacity>
+                </View>
+              </View>
+            </TouchableWithoutFeedback>
+          </View>
+        </TouchableWithoutFeedback>
+      </Modal>
+
+      {/* Summary Result Modal */}
+      <Modal
+        visible={showSummaryResultModal}
+        transparent
+        animationType="slide"
+        onRequestClose={() => setShowSummaryResultModal(false)}
+      >
+        <TouchableWithoutFeedback onPress={() => setShowSummaryResultModal(false)}>
+          <View style={styles.modalOverlay}>
+            <TouchableWithoutFeedback onPress={e => e.stopPropagation()}>
+              <View style={[styles.modalContent, { maxHeight: '70%' }]}>
+                <View style={styles.modalHandle} />
+                <View style={styles.modalHeader}>
+                  <Text style={styles.modalTitle}>Conversation Summary</Text>
+                  <TouchableOpacity onPress={() => setShowSummaryResultModal(false)}>
+                    <Ionicons name="close" size={24} color={colors.flow.textSecondary} />
+                  </TouchableOpacity>
+                </View>
+
+                <ScrollView style={styles.summaryContainer} showsVerticalScrollIndicator={false}>
+                  <View style={styles.summaryCard}>
+                    <Text style={styles.summaryText}>{generatedSummary}</Text>
+                  </View>
+                </ScrollView>
+
+                <View style={styles.summaryActions}>
+                  <TouchableOpacity
+                    style={[styles.actionButton, styles.saveToVaultButton]}
+                    onPress={() => setShowVaultConfirmModal(true)}
+                    disabled={isSavingToVault}
+                  >
+                    <LinearGradient
+                      colors={[colors.nautical.teal, colors.nautical.seafoam]}
+                      style={styles.actionButtonGradient}
+                    >
+                      {isSavingToVault ? (
+                        <ActivityIndicator size="small" color="#fff" />
+                      ) : (
+                        <>
+                          <Ionicons name="shield-checkmark-outline" size={20} color="#fff" />
+                          <Text style={styles.confirmButtonText}>Save to Vault</Text>
+                        </>
+                      )}
+                    </LinearGradient>
+                  </TouchableOpacity>
+
+                  <TouchableOpacity
+                    style={styles.closeButton}
+                    onPress={() => setShowSummaryResultModal(false)}
+                  >
+                    <Text style={styles.closeButtonText}>Done</Text>
+                  </TouchableOpacity>
+                </View>
+              </View>
+            </TouchableWithoutFeedback>
+          </View>
+        </TouchableWithoutFeedback>
+      </Modal>
+
+      {/* Save to Vault Confirmation Modal */}
+      <Modal
+        visible={showVaultConfirmModal}
+        transparent
+        animationType="fade"
+        onRequestClose={() => setShowVaultConfirmModal(false)}
+      >
+        <TouchableWithoutFeedback onPress={() => setShowVaultConfirmModal(false)}>
+          <View style={styles.modalOverlay}>
+            <TouchableWithoutFeedback onPress={e => e.stopPropagation()}>
+              <View style={[styles.modalContent, { paddingBottom: spacing.xl }]}>
+                <View style={styles.modalHandle} />
+                <Text style={styles.modalTitle}>Save to Vault</Text>
+                <Text style={[styles.modalSubtitle, { marginVertical: spacing.base }]}>
+                  Would you like to securely save this summary to your digital vault?
+                </Text>
+
+                <View style={styles.modalActions}>
+                  <TouchableOpacity
+                    style={[styles.actionButton, styles.cancelButton]}
+                    onPress={() => setShowVaultConfirmModal(false)}
+                  >
+                    <Text style={styles.cancelButtonText}>Cancel</Text>
+                  </TouchableOpacity>
+                  <TouchableOpacity
+                    style={[styles.actionButton, styles.confirmButton]}
+                    onPress={handleSaveToVault}
+                  >
+                    <LinearGradient
+                      colors={[colors.nautical.teal, colors.nautical.seafoam]}
+                      style={styles.actionButtonGradient}
+                    >
+                      <Text style={styles.confirmButtonText}>Yes, Save</Text>
+                    </LinearGradient>
+                  </TouchableOpacity>
+                </View>
+              </View>
+            </TouchableWithoutFeedback>
+          </View>
+        </TouchableWithoutFeedback>
+      </Modal>
+
+      {/* Save Result Modal */}
+      <Modal
+        visible={showSaveResultModal}
+        transparent
+        animationType="fade"
+        onRequestClose={handleFinishSaveFlow}
+      >
+        <TouchableWithoutFeedback onPress={handleFinishSaveFlow}>
+          <View style={styles.modalOverlay}>
+            <TouchableWithoutFeedback onPress={e => e.stopPropagation()}>
+              <View style={[styles.modalContent, { paddingBottom: spacing.xl, alignItems: 'center' }]}>
+                <View style={styles.modalHandle} />
+
+                <View style={[
+                  styles.resultIconContainer,
+                  saveResult.success ? styles.successIconBg : styles.errorIconBg
+                ]}>
+                  <Ionicons
+                    name={saveResult.success ? "checkmark-circle" : "alert-circle"}
+                    size={64}
+                    color={saveResult.success ? colors.nautical.teal : colors.nautical.coral}
+                  />
+                </View>
+
+                <Text style={styles.modalTitle}>
+                  {saveResult.success ? 'Success!' : 'Oops!'}
+                </Text>
+
+                <Text style={[styles.modalSubtitle, { marginVertical: spacing.base, textAlign: 'center' }]}>
+                  {saveResult.message}
+                </Text>
+
+                <TouchableOpacity
+                  style={[styles.actionButton, styles.confirmButton, { width: '100%' }]}
+                  onPress={handleFinishSaveFlow}
+                >
+                  <LinearGradient
+                    colors={[colors.nautical.teal, colors.nautical.seafoam]}
+                    style={styles.actionButtonGradient}
+                  >
+                    <Text style={styles.confirmButtonText}>Confirm</Text>
+                  </LinearGradient>
+                </TouchableOpacity>
+              </View>
+            </TouchableWithoutFeedback>
+          </View>
+        </TouchableWithoutFeedback>
+      </Modal>
+
+      {/* Summary Loading Modal */}
+      <Modal
+        visible={isSummarizing}
+        transparent
+        animationType="fade"
+      >
+        <View style={styles.loadingOverlay}>
+          <View style={styles.loadingContainer}>
+            <ActivityIndicator size="large" color={colors.nautical.teal} />
+            <Text style={styles.loadingText}>Generating Summary...</Text>
+          </View>
+        </View>
+      </Modal>
     </View>
   );
 }
@@ -697,12 +1274,33 @@ const styles = StyleSheet.create({
     alignItems: 'center',
     paddingHorizontal: spacing.base,
     paddingTop: spacing.sm,
-    paddingBottom: spacing.md,
+    paddingBottom: spacing.sm,
+    borderBottomWidth: 1,
+    borderBottomColor: 'rgba(0,0,0,0.05)',
   },
   headerLeft: {
     flexDirection: 'row',
     alignItems: 'center',
     gap: spacing.sm,
+    flex: 1,
+  },
+  headerRoleButton: {
+    flexDirection: 'row',
+    alignItems: 'center',
+    backgroundColor: colors.flow.cardBackground,
+    paddingHorizontal: spacing.sm,
+    paddingVertical: 6,
+    borderRadius: borderRadius.full,
+    marginHorizontal: spacing.sm,
+    borderWidth: 1,
+    borderColor: colors.flow.cardBorder,
+    maxWidth: '40%',
+  },
+  headerRoleText: {
+    fontSize: typography.fontSize.xs,
+    fontWeight: '600',
+    color: colors.flow.text,
+    marginHorizontal: 4,
   },
   iconCircle: {
     width: 44,
@@ -773,6 +1371,96 @@ const styles = StyleSheet.create({
     textAlign: 'center',
   },
 
+  // Role selection styles
+  roleDropdown: {
+    flexDirection: 'row',
+    alignItems: 'center',
+    backgroundColor: colors.flow.cardBackground,
+    paddingHorizontal: spacing.md,
+    paddingVertical: spacing.sm,
+    borderRadius: borderRadius.lg,
+    marginBottom: spacing.md,
+    ...shadows.soft,
+    borderWidth: 1,
+    borderColor: colors.flow.cardBorder,
+  },
+  roleIcon: {
+    marginRight: spacing.sm,
+  },
+  roleDropdownText: {
+    fontSize: typography.fontSize.base,
+    fontWeight: '600',
+    color: colors.flow.text,
+    marginRight: spacing.xs,
+  },
+  roleModalContent: {
+    paddingBottom: spacing.xl,
+  },
+  roleList: {
+    marginTop: spacing.sm,
+    maxHeight: 400,
+  },
+  roleItemContainer: {
+    marginBottom: spacing.sm,
+  },
+  roleItem: {
+    flexDirection: 'row',
+    alignItems: 'center',
+    justifyContent: 'space-between',
+    borderRadius: borderRadius.lg,
+    backgroundColor: 'transparent',
+    borderWidth: 1,
+    borderColor: 'transparent',
+    overflow: 'hidden',
+  },
+  roleItemActive: {
+    backgroundColor: colors.nautical.paleAqua,
+    borderColor: colors.nautical.lightMint,
+  },
+  roleSelectionArea: {
+    flex: 1,
+    flexDirection: 'row',
+    alignItems: 'center',
+    padding: spacing.md,
+  },
+  roleItemIcon: {
+    width: 36,
+    height: 36,
+    borderRadius: 18,
+    backgroundColor: colors.flow.backgroundGradientStart,
+    justifyContent: 'center',
+    alignItems: 'center',
+    marginRight: spacing.md,
+  },
+  roleItemIconActive: {
+    backgroundColor: colors.nautical.teal,
+  },
+  roleItemName: {
+    fontSize: typography.fontSize.base,
+    fontWeight: '500',
+    color: colors.flow.text,
+  },
+  roleItemNameActive: {
+    fontWeight: '700',
+    color: colors.nautical.teal,
+  },
+  infoButton: {
+    padding: spacing.md,
+    justifyContent: 'center',
+    alignItems: 'center',
+  },
+  roleDescription: {
+    paddingHorizontal: spacing.md + 36 + spacing.md, // icon width + margins
+    paddingBottom: spacing.sm,
+    paddingTop: 0,
+  },
+  roleDescriptionText: {
+    fontSize: typography.fontSize.sm,
+    color: colors.flow.textSecondary,
+    fontStyle: 'italic',
+    lineHeight: 18,
+  },
+
   // Message bubble styles
   messageBubble: {
     flexDirection: 'row',
@@ -997,4 +1685,101 @@ const styles = StyleSheet.create({
     color: colors.flow.textSecondary,
     fontWeight: '600',
   },
+
+  // Summary Modal styles
+  modalSubtitle: {
+    fontSize: typography.fontSize.base,
+    color: colors.flow.textSecondary,
+    lineHeight: 22,
+  },
+  modalActions: {
+    flexDirection: 'row',
+    gap: spacing.md,
+    marginTop: spacing.base,
+  },
+  actionButton: {
+    flex: 1,
+    height: 50,
+    borderRadius: borderRadius.lg,
+    justifyContent: 'center',
+    alignItems: 'center',
+    overflow: 'hidden',
+  },
+  actionButtonGradient: {
+    width: '100%',
+    height: '100%',
+    justifyContent: 'center',
+    alignItems: 'center',
+  },
+  cancelButton: {
+    backgroundColor: colors.nautical.paleAqua,
+  },
+  confirmButton: {
+    // Gradient handled in child
+  },
+  cancelButtonText: {
+    fontSize: typography.fontSize.base,
+    fontWeight: '600',
+    color: colors.flow.textSecondary,
+  },
+  confirmButtonText: {
+    fontSize: typography.fontSize.base,
+    fontWeight: '600',
+    color: '#fff',
+  },
+  summaryContainer: {
+    marginVertical: spacing.md,
+  },
+  summaryCard: {
+    backgroundColor: colors.nautical.paleAqua + '40', // 25% opacity
+    padding: spacing.md,
+    borderRadius: borderRadius.lg,
+    borderWidth: 1,
+    borderColor: colors.nautical.lightMint,
+  },
+  summaryText: {
+    fontSize: typography.fontSize.base,
+    color: colors.flow.text,
+    lineHeight: 24,
+  },
+  summaryActions: {
+    marginTop: spacing.md,
+    gap: spacing.sm,
+  },
+  saveToVaultButton: {
+    height: 54,
+  },
+  resultIconContainer: {
+    width: 80,
+    height: 80,
+    borderRadius: 40,
+    justifyContent: 'center',
+    alignItems: 'center',
+    marginBottom: spacing.md,
+  },
+  successIconBg: {
+    backgroundColor: colors.nautical.paleAqua,
+  },
+  errorIconBg: {
+    backgroundColor: 'rgba(231, 76, 60, 0.1)', // coral at 10%
+  },
+  loadingOverlay: {
+    flex: 1,
+    backgroundColor: 'rgba(26, 58, 74, 0.6)',
+    justifyContent: 'center',
+    alignItems: 'center',
+  },
+  loadingContainer: {
+    backgroundColor: colors.flow.cardBackground,
+    padding: spacing.xl,
+    borderRadius: borderRadius.xl,
+    alignItems: 'center',
+    ...shadows.soft,
+    gap: spacing.md,
+  },
+  loadingText: {
+    fontSize: typography.fontSize.base,
+    color: colors.flow.text,
+    fontWeight: '600',
+  },
 });

src/screens/MeScreen.tsx

@@ -14,9 +14,11 @@ import {
 import { LinearGradient } from 'expo-linear-gradient';
 import { Ionicons, Feather, MaterialCommunityIcons, FontAwesome5 } from '@expo/vector-icons';
 import { colors, typography, spacing, borderRadius, shadows } from '../theme/colors';
+import AsyncStorage from '@react-native-async-storage/async-storage';
 import { useAuth } from '../context/AuthContext';
 import { Heir, HeirStatus, PaymentStrategy } from '../types';
 import HeritageScreen from './HeritageScreen';
+import { getVaultStorageKeys } from '../config';
 
 // Mock heirs data
 const initialHeirs: Heir[] = [
@@ -220,6 +222,7 @@ export default function MeScreen() {
   const [showHeritageModal, setShowHeritageModal] = useState(false);
   const [showThemeModal, setShowThemeModal] = useState(false);
   const [isDarkMode, setIsDarkMode] = useState(false);
+  const [showSignOutModal, setShowSignOutModal] = useState(false);
 
   // Heritage / Fleet Legacy states
   const [heirs, setHeirs] = useState<Heir[]>(initialHeirs);
@@ -245,6 +248,7 @@ export default function MeScreen() {
   });
   const [sanctumArchive, setSanctumArchive] = useState<'off' | 'standard' | 'strict'>('standard');
   const [sanctumRehearsal, setSanctumRehearsal] = useState<'monthly' | 'quarterly'>('quarterly');
+  const [resetVaultFeedback, setResetVaultFeedback] = useState<{ status: 'idle' | 'success' | 'error'; message: string }>({ status: 'idle', message: '' });
   const [triggerDisconnectDays, setTriggerDisconnectDays] = useState(30);
   const [triggerGraceDays, setTriggerGraceDays] = useState(15);
   const [triggerSource, setTriggerSource] = useState<'dual' | 'subscription' | 'activity'>('dual');
@@ -294,18 +298,40 @@ export default function MeScreen() {
   };
 
   const handleAbandonIsland = () => {
-    Alert.alert(
+    console.log('[MeScreen] Sign out button clicked');
-      'Sign Out',
+    setShowSignOutModal(true);
-      'Are you sure you want to sign out?',
+  };
-      [
+
-        { text: 'Cancel', style: 'cancel' },
+  const handleConfirmSignOut = () => {
-        {
+    console.log('[MeScreen] User confirmed sign out');
-          text: 'Sign Out',
+    setShowSignOutModal(false);
-          style: 'destructive',
+    signOut();
-          onPress: signOut
+  };
-        },
+
-      ]
+  const handleResetVault = async () => {
-    );
+    setResetVaultFeedback({ status: 'idle', message: '' });
+    const vaultKeys = getVaultStorageKeys(user?.id ?? null);
+    try {
+      await AsyncStorage.multiRemove([
+        vaultKeys.INITIALIZED,
+        vaultKeys.SHARE_DEVICE,
+        vaultKeys.MNEMONIC_PART_LOCAL,
+      ]);
+      setResetVaultFeedback({
+        status: 'success',
+        message: 'Vault state has been reset. Next time you open Shadow Vault you will see the mnemonic flow again.',
+      });
+    } catch (e) {
+      setResetVaultFeedback({
+        status: 'error',
+        message: 'Failed to reset vault state. Please try again.',
+      });
+    }
+  };
+
+  const handleCloseSanctumModal = () => {
+    setResetVaultFeedback({ status: 'idle', message: '' });
+    setShowSanctumModal(false);
   };
 
   return (
@@ -749,7 +775,7 @@ export default function MeScreen() {
         visible={showSanctumModal}
         animationType="fade"
         transparent
-        onRequestClose={() => setShowSanctumModal(false)}
+        onRequestClose={handleCloseSanctumModal}
       >
         <View style={styles.spiritOverlay}>
           <View style={styles.spiritModal}>
@@ -885,12 +911,51 @@ export default function MeScreen() {
                   <Text style={styles.sanctumValue}>View</Text>
                 </View>
               </View>
+
+              {__DEV__ && (
+                <View style={styles.sanctumSection}>
+                  <Text style={styles.tideLabel}>DEV ONLY</Text>
+                  <TouchableOpacity
+                    style={styles.devResetButton}
+                    onPress={handleResetVault}
+                    activeOpacity={0.85}
+                  >
+                    <Ionicons name="refresh" size={16} color={colors.nautical.coral} />
+                    <Text style={styles.devResetText}>Reset Vault State</Text>
+                  </TouchableOpacity>
+                  <Text style={styles.sanctumHint}>Clear S0 (SHARE_DEVICE) from storage. Next vault open uses mnemonic flow.</Text>
+                  {resetVaultFeedback.status !== 'idle' && (
+                    <View
+                      style={[
+                        styles.resetVaultFeedback,
+                        resetVaultFeedback.status === 'success' ? styles.resetVaultFeedbackSuccess : styles.resetVaultFeedbackError,
+                      ]}
+                    >
+                      <Ionicons
+                        name={resetVaultFeedback.status === 'success' ? 'checkmark-circle' : 'alert-circle'}
+                        size={20}
+                        color={resetVaultFeedback.status === 'success' ? colors.sentinel?.statusNormal ?? '#6BBF8A' : colors.nautical.coral}
+                      />
+                      <Text
+                        style={[
+                          styles.resetVaultFeedbackText,
+                          resetVaultFeedback.status === 'success' ? styles.resetVaultFeedbackTextSuccess : styles.resetVaultFeedbackTextError,
+                        ]}
+                      >
+                        {resetVaultFeedback.status === 'success' ? 'Success' : 'Error'}
+                        {' — '}
+                        {resetVaultFeedback.message}
+                      </Text>
+                    </View>
+                  )}
+                </View>
+              )}
             </ScrollView>
             <View style={styles.tideModalButtons}>
               <TouchableOpacity
                 style={styles.confirmPulseButton}
                 activeOpacity={0.85}
-                onPress={() => setShowSanctumModal(false)}
+                onPress={handleCloseSanctumModal}
               >
                 <Ionicons name="checkmark-circle" size={18} color={colors.nautical.teal} />
                 <Text style={styles.confirmPulseText}>Save</Text>
@@ -898,7 +963,7 @@ export default function MeScreen() {
               <TouchableOpacity
                 style={styles.confirmPulseButton}
                 activeOpacity={0.85}
-                onPress={() => setShowSanctumModal(false)}
+                onPress={handleCloseSanctumModal}
               >
                 <Ionicons name="close-circle" size={18} color={colors.nautical.teal} />
                 <Text style={styles.confirmPulseText}>Close</Text>
@@ -1412,6 +1477,46 @@ export default function MeScreen() {
           </View>
         </View>
       </Modal>
+
+      {/* Sign Out Confirmation Modal */}
+      <Modal
+        visible={showSignOutModal}
+        animationType="fade"
+        transparent
+        onRequestClose={() => setShowSignOutModal(false)}
+      >
+        <View style={styles.spiritOverlay}>
+          <View style={styles.signOutModal}>
+            <View style={styles.signOutHeader}>
+              <View style={styles.signOutIcon}>
+                <Feather name="log-out" size={32} color={colors.nautical.coral} />
+              </View>
+              <Text style={styles.signOutTitle}>Sign Out</Text>
+              <Text style={styles.signOutMessage}>
+                Are you sure you want to sign out? You'll need to log in again to access your account.
+              </Text>
+            </View>
+
+            <View style={styles.signOutButtons}>
+              <TouchableOpacity
+                style={styles.signOutCancelButton}
+                onPress={() => setShowSignOutModal(false)}
+                activeOpacity={0.85}
+              >
+                <Text style={styles.signOutCancelText}>Cancel</Text>
+              </TouchableOpacity>
+
+              <TouchableOpacity
+                style={styles.signOutConfirmButton}
+                onPress={handleConfirmSignOut}
+                activeOpacity={0.85}
+              >
+                <Text style={styles.signOutConfirmText}>Sign Out</Text>
+              </TouchableOpacity>
+            </View>
+          </View>
+        </View>
+      </Modal>
     </View>
   );
 }
@@ -1814,6 +1919,23 @@ const styles = StyleSheet.create({
     fontSize: typography.fontSize.sm,
     color: colors.me.textSecondary,
   },
+  devResetButton: {
+    flexDirection: 'row',
+    alignItems: 'center',
+    gap: spacing.sm,
+    paddingVertical: spacing.sm,
+    paddingHorizontal: spacing.md,
+    backgroundColor: `${colors.nautical.coral}15`,
+    borderRadius: borderRadius.lg,
+    borderWidth: 1,
+    borderColor: `${colors.nautical.coral}40`,
+    alignSelf: 'flex-start',
+  },
+  devResetText: {
+    fontSize: typography.fontSize.sm,
+    color: colors.nautical.coral,
+    fontWeight: '600',
+  },
   sanctumAlert: {
     flexDirection: 'row',
     alignItems: 'center',
@@ -1827,6 +1949,34 @@ const styles = StyleSheet.create({
     fontSize: typography.fontSize.sm,
     color: colors.nautical.coral,
   },
+  resetVaultFeedback: {
+    flexDirection: 'row',
+    alignItems: 'center',
+    gap: spacing.sm,
+    borderRadius: borderRadius.lg,
+    padding: spacing.base,
+    marginTop: spacing.md,
+  },
+  resetVaultFeedbackSuccess: {
+    backgroundColor: 'rgba(107, 191, 138, 0.2)',
+    borderWidth: 1,
+    borderColor: 'rgba(107, 191, 138, 0.5)',
+  },
+  resetVaultFeedbackError: {
+    backgroundColor: 'rgba(229, 115, 115, 0.2)',
+    borderWidth: 1,
+    borderColor: 'rgba(229, 115, 115, 0.5)',
+  },
+  resetVaultFeedbackText: {
+    flex: 1,
+    fontSize: typography.fontSize.sm,
+  },
+  resetVaultFeedbackTextSuccess: {
+    color: '#2E7D5E',
+  },
+  resetVaultFeedbackTextError: {
+    color: colors.nautical.coral,
+  },
   confirmPulseButton: {
     flexDirection: 'row',
     alignItems: 'center',
@@ -2333,4 +2483,71 @@ const styles = StyleSheet.create({
     justifyContent: 'center',
     zIndex: 10,
   },
+  // Sign Out Modal Styles
+  signOutModal: {
+    backgroundColor: colors.me.cardBackground,
+    borderRadius: borderRadius.xl,
+    padding: spacing.xl,
+    marginHorizontal: spacing.xl,
+    maxWidth: 400,
+    width: '100%',
+    ...shadows.medium,
+  },
+  signOutHeader: {
+    alignItems: 'center',
+    marginBottom: spacing.xl,
+  },
+  signOutIcon: {
+    width: 72,
+    height: 72,
+    borderRadius: 36,
+    backgroundColor: `${colors.nautical.coral}15`,
+    alignItems: 'center',
+    justifyContent: 'center',
+    marginBottom: spacing.base,
+  },
+  signOutTitle: {
+    fontSize: typography.fontSize.xl,
+    fontWeight: '700',
+    color: colors.me.text,
+    marginBottom: spacing.sm,
+  },
+  signOutMessage: {
+    fontSize: typography.fontSize.base,
+    color: colors.me.textSecondary,
+    textAlign: 'center',
+    lineHeight: typography.fontSize.base * 1.5,
+  },
+  signOutButtons: {
+    flexDirection: 'row',
+    gap: spacing.md,
+  },
+  signOutCancelButton: {
+    flex: 1,
+    paddingVertical: spacing.base,
+    paddingHorizontal: spacing.lg,
+    borderRadius: borderRadius.lg,
+    backgroundColor: colors.me.cardBorder,
+    alignItems: 'center',
+    justifyContent: 'center',
+  },
+  signOutCancelText: {
+    fontSize: typography.fontSize.base,
+    fontWeight: '600',
+    color: colors.me.text,
+  },
+  signOutConfirmButton: {
+    flex: 1,
+    paddingVertical: spacing.base,
+    paddingHorizontal: spacing.lg,
+    borderRadius: borderRadius.lg,
+    backgroundColor: colors.nautical.coral,
+    alignItems: 'center',
+    justifyContent: 'center',
+  },
+  signOutConfirmText: {
+    fontSize: typography.fontSize.base,
+    fontWeight: '600',
+    color: '#fff',
+  },
 });

src/screens/SentinelScreen.tsx

@@ -1,4 +1,4 @@
-import React, { useState, useEffect, useRef } from 'react';
+import React, { useState, useEffect } from 'react';
 import {
   View,
   Text,
@@ -8,40 +8,12 @@ import {
   SafeAreaView,
   Animated,
   Modal,
-  TextInput,
-  KeyboardAvoidingView,
-  Platform,
-  Share,
-  Alert,
-  Linking,
 } from 'react-native';
 import { LinearGradient } from 'expo-linear-gradient';
 import { Ionicons, Feather, MaterialCommunityIcons, FontAwesome5 } from '@expo/vector-icons';
-import { captureRef } from 'react-native-view-shot';
-import AsyncStorage from '@react-native-async-storage/async-storage';
 import { colors, typography, spacing, borderRadius, shadows } from '../theme/colors';
 import { SystemStatus, KillSwitchLog } from '../types';
 import VaultScreen from './VaultScreen';
-import {
-  SSSShare,
-  mnemonicToEntropy,
-  splitSecret,
-  formatShareCompact,
-  serializeShare,
-  verifyShares,
-} from '../utils/sss';
-
-// Nautical-themed mnemonic word list (unique words only)
-const MNEMONIC_WORDS = [
-  'anchor', 'harbor', 'compass', 'lighthouse', 'current', 'ocean', 'tide', 'voyage',
-  'keel', 'stern', 'bow', 'mast', 'sail', 'port', 'starboard', 'reef',
-  'signal', 'beacon', 'chart', 'helm', 'gale', 'calm', 'cove', 'isle',
-  'horizon', 'sextant', 'sound', 'drift', 'wake', 'mariner', 'pilot', 'fathom',
-  'buoy', 'lantern', 'harpoon', 'lagoon', 'bay', 'strait', 'riptide', 'foam',
-  'coral', 'pearl', 'trident', 'ebb', 'flow', 'vault', 'cipher', 'shroud',
-  'salt', 'wave', 'grotto', 'storm', 'north', 'south', 'east', 'west',
-  'ember', 'cabin', 'ledger', 'torch', 'sanctum', 'oath', 'depths', 'captain',
-] as const;
 
 // Animation timing constants
 const ANIMATION_DURATION = {
@@ -51,49 +23,6 @@ const ANIMATION_DURATION = {
   heartbeatPress: 150,
 } as const;
 
-const generateMnemonic = (wordCount = 12) => {
-  const words: string[] = [];
-  for (let i = 0; i < wordCount; i += 1) {
-    const index = Math.floor(Math.random() * MNEMONIC_WORDS.length);
-    words.push(MNEMONIC_WORDS[index]);
-  }
-  return words;
-};
-
-/**
- * Generate SSS shares from mnemonic words
- * Uses Shamir's Secret Sharing (3,2) threshold scheme
- */
-const generateSSSShares = (words: string[]): SSSShare[] => {
-  try {
-    // Convert mnemonic to entropy (big integer)
-    const entropy = mnemonicToEntropy(words, MNEMONIC_WORDS);
-    
-    // Split entropy into 3 shares using SSS
-    const shares = splitSecret(entropy);
-    
-    // Verify shares can recover the original (optional, for debugging)
-    if (__DEV__) {
-      const isValid = verifyShares(shares, entropy);
-      if (!isValid) {
-        console.warn('SSS verification failed!');
-      } else {
-        console.log('SSS shares verified successfully');
-      }
-    }
-    
-    return shares;
-  } catch (error) {
-    console.error('Failed to generate SSS shares:', error);
-    // Fallback: return empty shares (should not happen in production)
-    return [
-      { x: 1, y: BigInt(0), label: 'device' },
-      { x: 2, y: BigInt(0), label: 'cloud' },
-      { x: 3, y: BigInt(0), label: 'heir' },
-    ];
-  }
-};
-
 // Icon names type for type safety
 type StatusIconName = 'checkmark-circle' | 'warning' | 'alert-circle';
 
@@ -130,28 +59,14 @@ const statusConfig: Record<SystemStatus, {
 
 // Mock data
 const initialLogs: KillSwitchLog[] = [
-  {
+  { id: '1', action: 'HEARTBEAT_CONFIRMED', timestamp: new Date('2024-01-18T09:30:00') },
-    id: '1',
+  { id: '2', action: 'SUBSCRIPTION_VERIFIED', timestamp: new Date('2024-01-17T00:00:00') },
-    action: 'HEARTBEAT_CONFIRMED',
+  { id: '3', action: 'JOURNAL_ACTIVITY', timestamp: new Date('2024-01-16T15:42:00') },
-    timestamp: new Date('2024-01-18T09:30:00'),
+  { id: '4', action: 'HEARTBEAT_CONFIRMED', timestamp: new Date('2024-01-15T11:20:00') },
-  },
-  {
-    id: '2',
-    action: 'SUBSCRIPTION_VERIFIED',
-    timestamp: new Date('2024-01-17T00:00:00'),
-  },
-  {
-    id: '3',
-    action: 'JOURNAL_ACTIVITY',
-    timestamp: new Date('2024-01-16T15:42:00'),
-  },
-  {
-    id: '4',
-    action: 'HEARTBEAT_CONFIRMED',
-    timestamp: new Date('2024-01-15T11:20:00'),
-  },
 ];
 
+export { VAULT_STORAGE_KEYS } from '../config';
+
 export default function SentinelScreen() {
   const [status, setStatus] = useState<SystemStatus>('normal');
   const [lastSubscriptionCheck] = useState(new Date('2024-01-18T00:00:00'));
@@ -161,16 +76,8 @@ export default function SentinelScreen() {
   const [glowAnim] = useState(new Animated.Value(0.5));
   const [rotateAnim] = useState(new Animated.Value(0));
   const [showVault, setShowVault] = useState(false);
-  const [showMnemonic, setShowMnemonic] = useState(false);
-  const [mnemonicWords, setMnemonicWords] = useState<string[]>([]);
-  const [sssShares, setSssShares] = useState<SSSShare[]>([]);
-  const [showEmailForm, setShowEmailForm] = useState(false);
-  const [emailAddress, setEmailAddress] = useState('');
-  const [isCapturing, setIsCapturing] = useState(false);
-  const mnemonicRef = useRef<View>(null);
 
   useEffect(() => {
-    // Pulse animation
     const pulseAnimation = Animated.loop(
       Animated.sequence([
         Animated.timing(pulseAnim, {
@@ -187,7 +94,6 @@ export default function SentinelScreen() {
     );
     pulseAnimation.start();
 
-    // Glow animation
     const glowAnimation = Animated.loop(
       Animated.sequence([
         Animated.timing(glowAnim, {
@@ -204,7 +110,6 @@ export default function SentinelScreen() {
     );
     glowAnimation.start();
 
-    // Slow rotate for ship wheel
     const rotateAnimation = Animated.loop(
       Animated.timing(rotateAnim, {
         toValue: 1,
@@ -214,7 +119,6 @@ export default function SentinelScreen() {
     );
     rotateAnimation.start();
 
-    // Cleanup animations on unmount to prevent memory leaks
     return () => {
       pulseAnimation.stop();
       glowAnimation.stop();
@@ -222,73 +126,9 @@ export default function SentinelScreen() {
     };
   }, [pulseAnim, glowAnim, rotateAnim]);
 
-  const openVaultWithMnemonic = () => {
+  const openVault = () => setShowVault(true);
-    const words = generateMnemonic();
-    const shares = generateSSSShares(words);
-    setMnemonicWords(words);
-    setSssShares(shares);
-    setShowMnemonic(true);
-    setShowVault(false);
-    setShowEmailForm(false);
-    setEmailAddress('');
-    
-    // Store Share A (device share) locally
-    if (shares[0]) {
-      AsyncStorage.setItem('sentinel_share_device', serializeShare(shares[0])).catch(() => {
-        // Best-effort local store; UI remains available
-      });
-    }
-  };
-
-  const handleScreenshot = async () => {
-    try {
-      setIsCapturing(true);
-      const uri = await captureRef(mnemonicRef, {
-        format: 'png',
-        quality: 1,
-        result: 'tmpfile',
-      });
-      await Share.share({
-        url: uri,
-        message: 'Sentinel key backup',
-      });
-      setShowMnemonic(false);
-      setShowVault(true);
-    } catch (error) {
-      Alert.alert('Screenshot failed', 'Please try again or use email backup.');
-    } finally {
-      setIsCapturing(false);
-    }
-  };
-
-  const handleEmailBackup = () => {
-    setShowEmailForm(true);
-  };
-
-  const handleSendEmail = async () => {
-    const trimmed = emailAddress.trim();
-    if (!trimmed || !/^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(trimmed)) {
-      Alert.alert('Invalid email', 'Please enter a valid email address.');
-      return;
-    }
-
-    const subject = encodeURIComponent('Sentinel Vault Recovery Key');
-    const body = encodeURIComponent(`Your 12-word mnemonic:\n${mnemonicWords.join(' ')}`);
-    const mailtoUrl = `mailto:${trimmed}?subject=${subject}&body=${body}`;
-
-    try {
-      await Linking.openURL(mailtoUrl);
-      setShowMnemonic(false);
-      setShowEmailForm(false);
-      setEmailAddress('');
-      setShowVault(true);
-    } catch (error) {
-      Alert.alert('Email failed', 'Unable to open email client.');
-    }
-  };
 
   const handleHeartbeat = () => {
-    // Animate pulse
     Animated.sequence([
       Animated.timing(pulseAnim, {
         toValue: 1.15,
@@ -302,7 +142,6 @@ export default function SentinelScreen() {
       }),
     ]).start();
 
-    // Add new log using functional update to avoid stale closure
     const newLog: KillSwitchLog = {
       id: Date.now().toString(),
       action: 'HEARTBEAT_CONFIRMED',
@@ -310,35 +149,27 @@ export default function SentinelScreen() {
     };
     setLogs((prevLogs) => [newLog, ...prevLogs]);
 
-    // Reset status if warning
     if (status === 'warning') {
       setStatus('normal');
     }
   };
 
-  const formatDateTime = (date: Date) => {
+  const formatDateTime = (date: Date) =>
-    return date.toLocaleString('en-US', {
+    date.toLocaleString('en-US', {
       year: 'numeric',
       month: '2-digit',
       day: '2-digit',
       hour: '2-digit',
       minute: '2-digit',
     });
-  };
 
   const formatTimeAgo = (date: Date) => {
     const now = new Date();
     const diff = now.getTime() - date.getTime();
     const hours = Math.floor(diff / (1000 * 60 * 60));
     const minutes = Math.floor((diff % (1000 * 60 * 60)) / (1000 * 60));
-    
+    if (hours > 24) return `${Math.floor(hours / 24)} days ago`;
-    if (hours > 24) {
+    if (hours > 0) return `${hours}h ${minutes}m ago`;
-      const days = Math.floor(hours / 24);
-      return `${days} days ago`;
-    }
-    if (hours > 0) {
-      return `${hours}h ${minutes}m ago`;
-    }
     return `${minutes}m ago`;
   };
 
@@ -378,7 +209,7 @@ export default function SentinelScreen() {
                     transform: [{ scale: pulseAnim }],
                     opacity: glowAnim,
                     backgroundColor: `${currentStatus.color}20`,
-                  }
+                  },
                 ]}
               />
               <Animated.View style={{ transform: [{ scale: pulseAnim }] }}>
@@ -416,24 +247,16 @@ export default function SentinelScreen() {
                   <FontAwesome5 name="anchor" size={16} color={colors.sentinel.primary} />
                 </View>
                 <Text style={styles.metricLabel}>SUBSCRIPTION</Text>
-                <Text style={styles.metricValue}>
+                <Text style={styles.metricValue}>{formatTimeAgo(lastSubscriptionCheck)}</Text>
-                  {formatTimeAgo(lastSubscriptionCheck)}
+                <Text style={styles.metricTime}>{formatDateTime(lastSubscriptionCheck)}</Text>
-                </Text>
-                <Text style={styles.metricTime}>
-                  {formatDateTime(lastSubscriptionCheck)}
-                </Text>
               </View>
               <View style={styles.metricCard}>
                 <View style={styles.metricIconContainer}>
                   <Feather name="edit-3" size={16} color={colors.sentinel.primary} />
                 </View>
                 <Text style={styles.metricLabel}>LAST JOURNAL</Text>
-                <Text style={styles.metricValue}>
+                <Text style={styles.metricValue}>{formatTimeAgo(lastFlowActivity)}</Text>
-                  {formatTimeAgo(lastFlowActivity)}
+                <Text style={styles.metricTime}>{formatDateTime(lastFlowActivity)}</Text>
-                </Text>
-                <Text style={styles.metricTime}>
-                  {formatDateTime(lastFlowActivity)}
-                </Text>
               </View>
             </View>
 
@@ -450,7 +273,7 @@ export default function SentinelScreen() {
               </View>
               <TouchableOpacity
                 style={styles.vaultAccessButton}
-                onPress={openVaultWithMnemonic}
+                onPress={openVault}
                 activeOpacity={0.8}
                 accessibilityLabel="Open Shadow Vault"
                 accessibilityRole="button"
@@ -494,9 +317,7 @@ export default function SentinelScreen() {
                   <View style={styles.logDot} />
                   <View style={styles.logContent}>
                     <Text style={styles.logAction}>{log.action}</Text>
-                    <Text style={styles.logTime}>
+                    <Text style={styles.logTime}>{formatDateTime(log.timestamp)}</Text>
-                      {formatDateTime(log.timestamp)}
-                    </Text>
                   </View>
                 </View>
               ))}
@@ -512,7 +333,7 @@ export default function SentinelScreen() {
         onRequestClose={() => setShowVault(false)}
       >
         <View style={styles.vaultModalContainer}>
-          <VaultScreen />
+          {showVault ? <VaultScreen /> : null}
           <TouchableOpacity
             style={styles.vaultCloseButton}
             onPress={() => setShowVault(false)}
@@ -524,140 +345,20 @@ export default function SentinelScreen() {
           </TouchableOpacity>
         </View>
       </Modal>
-
-      {/* Mnemonic Modal */}
-      <Modal
-        visible={showMnemonic}
-        animationType="fade"
-        transparent
-        onRequestClose={() => setShowMnemonic(false)}
-      >
-        <KeyboardAvoidingView
-          style={styles.mnemonicOverlay}
-          behavior={Platform.OS === 'ios' ? 'padding' : undefined}
-        >
-          <View ref={mnemonicRef} collapsable={false}>
-            <LinearGradient
-              colors={[colors.sentinel.cardBackground, colors.sentinel.backgroundGradientEnd]}
-              style={styles.mnemonicCard}
-            >
-            <TouchableOpacity
-              style={styles.mnemonicClose}
-              onPress={() => setShowMnemonic(false)}
-              activeOpacity={0.85}
-              accessibilityLabel="Close mnemonic modal"
-              accessibilityRole="button"
-            >
-              <Ionicons name="close" size={18} color={colors.sentinel.textSecondary} />
-            </TouchableOpacity>
-            <View style={styles.mnemonicHeader}>
-              <MaterialCommunityIcons name="key-variant" size={22} color={colors.sentinel.primary} />
-              <Text style={styles.mnemonicTitle}>12-Word Mnemonic</Text>
-            </View>
-            <Text style={styles.mnemonicSubtitle}>
-              Your seed is protected by SSS (3,2) threshold encryption. Any 2 shares can restore your vault.
-            </Text>
-            <View style={styles.mnemonicBlock}>
-              <Text style={styles.mnemonicBlockText}>
-                {mnemonicWords.join(' ')}
-              </Text>
-            </View>
-            <View style={styles.partGrid}>
-              <View style={[styles.partCard, styles.partCardStored]}>
-                <Text style={styles.partLabel}>SHARE A • DEVICE</Text>
-                <Text style={styles.partValue}>
-                  {sssShares[0] ? formatShareCompact(sssShares[0]) : '---'}
-                </Text>
-                <Text style={styles.partHint}>Stored on this device</Text>
-              </View>
-              <View style={styles.partCard}>
-                <Text style={styles.partLabel}>SHARE B • CLOUD</Text>
-                <Text style={styles.partValue}>
-                  {sssShares[1] ? formatShareCompact(sssShares[1]) : '---'}
-                </Text>
-                <Text style={styles.partHint}>To be synced to Sentinel</Text>
-              </View>
-              <View style={styles.partCard}>
-                <Text style={styles.partLabel}>SHARE C • HEIR</Text>
-                <Text style={styles.partValue}>
-                  {sssShares[2] ? formatShareCompact(sssShares[2]) : '---'}
-                </Text>
-                <Text style={styles.partHint}>For your heir (2-of-3 required)</Text>
-              </View>
-            </View>
-            <TouchableOpacity
-              style={[styles.mnemonicPrimaryButton, isCapturing && styles.mnemonicButtonDisabled]}
-              onPress={handleScreenshot}
-              activeOpacity={0.85}
-              disabled={isCapturing}
-              accessibilityLabel="Take screenshot backup of mnemonic"
-              accessibilityRole="button"
-              accessibilityState={{ disabled: isCapturing }}
-            >
-              <Text style={styles.mnemonicPrimaryText}>
-                {isCapturing ? 'CAPTURING...' : 'PHYSICAL BACKUP (SCREENSHOT)'}
-              </Text>
-            </TouchableOpacity>
-            <TouchableOpacity
-              style={styles.mnemonicSecondaryButton}
-              onPress={handleEmailBackup}
-              activeOpacity={0.85}
-              accessibilityLabel="Send mnemonic backup via email"
-              accessibilityRole="button"
-            >
-              <Text style={styles.mnemonicSecondaryText}>EMAIL BACKUP</Text>
-            </TouchableOpacity>
-            {showEmailForm ? (
-              <View style={styles.emailForm}>
-                <TextInput
-                  style={styles.emailInput}
-                  value={emailAddress}
-                  onChangeText={setEmailAddress}
-                  placeholder="you@email.com"
-                  placeholderTextColor={colors.sentinel.textSecondary}
-                  keyboardType="email-address"
-                  autoCapitalize="none"
-                  autoCorrect={false}
-                />
-                <TouchableOpacity
-                  style={styles.emailSendButton}
-                  onPress={handleSendEmail}
-                  activeOpacity={0.85}
-                  accessibilityLabel="Send backup email"
-                  accessibilityRole="button"
-                >
-                  <Text style={styles.emailSendText}>SEND EMAIL</Text>
-                </TouchableOpacity>
-              </View>
-            ) : null}
-            </LinearGradient>
-          </View>
-        </KeyboardAvoidingView>
-      </Modal>
     </View>
   );
 }
 
 const styles = StyleSheet.create({
-  container: {
+  container: { flex: 1 },
-    flex: 1,
+  gradient: { flex: 1 },
-  },
+  safeArea: { flex: 1 },
-  gradient: {
+  scrollView: { flex: 1 },
-    flex: 1,
-  },
-  safeArea: {
-    flex: 1,
-  },
-  scrollView: {
-    flex: 1,
-  },
   scrollContent: {
     padding: spacing.lg,
     paddingBottom: 120,
   },
-  header: {
+  header: { marginBottom: spacing.xl },
-    marginBottom: spacing.xl,
-  },
   headerTitleRow: {
     flexDirection: 'row',
     alignItems: 'center',
@@ -763,9 +464,7 @@ const styles = StyleSheet.create({
     marginBottom: spacing.xl,
     ...shadows.medium,
   },
-  heartbeatGradient: {
+  heartbeatGradient: { padding: spacing.lg },
-    padding: spacing.lg,
-  },
   heartbeatContent: {
     flexDirection: 'row',
     alignItems: 'center',
@@ -819,9 +518,7 @@ const styles = StyleSheet.create({
     marginTop: 6,
     marginRight: spacing.md,
   },
-  logContent: {
+  logContent: { flex: 1 },
-    flex: 1,
-  },
   logAction: {
     fontSize: typography.fontSize.sm,
     color: colors.sentinel.text,
@@ -834,7 +531,6 @@ const styles = StyleSheet.create({
     color: colors.sentinel.textSecondary,
     fontFamily: typography.fontFamily.mono,
   },
-  // Shadow Vault Access Card
   vaultAccessCard: {
     flexDirection: 'row',
     alignItems: 'center',
@@ -854,9 +550,7 @@ const styles = StyleSheet.create({
     justifyContent: 'center',
     marginRight: spacing.md,
   },
-  vaultAccessContent: {
+  vaultAccessContent: { flex: 1 },
-    flex: 1,
-  },
   vaultAccessTitle: {
     fontSize: typography.fontSize.base,
     fontWeight: '600',
@@ -878,7 +572,6 @@ const styles = StyleSheet.create({
     fontWeight: '700',
     fontSize: typography.fontSize.sm,
   },
-  // Vault Modal
   vaultModalContainer: {
     flex: 1,
     backgroundColor: colors.vault.background,
@@ -894,148 +587,4 @@ const styles = StyleSheet.create({
     alignItems: 'center',
     justifyContent: 'center',
   },
-  mnemonicOverlay: {
-    flex: 1,
-    backgroundColor: 'rgba(11, 20, 24, 0.72)',
-    justifyContent: 'center',
-    padding: spacing.lg,
-  },
-  mnemonicCard: {
-    borderRadius: borderRadius.xl,
-    padding: spacing.lg,
-    borderWidth: 1,
-    borderColor: colors.sentinel.cardBorder,
-    ...shadows.glow,
-  },
-  mnemonicHeader: {
-    flexDirection: 'row',
-    alignItems: 'center',
-    gap: spacing.sm,
-    marginBottom: spacing.sm,
-  },
-  mnemonicClose: {
-    position: 'absolute',
-    top: spacing.sm,
-    right: spacing.sm,
-    width: 32,
-    height: 32,
-    borderRadius: 16,
-    alignItems: 'center',
-    justifyContent: 'center',
-    backgroundColor: 'rgba(26, 58, 74, 0.35)',
-  },
-  mnemonicTitle: {
-    fontSize: typography.fontSize.lg,
-    fontWeight: '700',
-    color: colors.sentinel.text,
-    letterSpacing: typography.letterSpacing.wide,
-  },
-  mnemonicSubtitle: {
-    fontSize: typography.fontSize.sm,
-    color: colors.sentinel.textSecondary,
-    marginBottom: spacing.md,
-  },
-  mnemonicBlock: {
-    backgroundColor: colors.sentinel.cardBackground,
-    borderRadius: borderRadius.lg,
-    paddingVertical: spacing.md,
-    paddingHorizontal: spacing.md,
-    borderWidth: 1,
-    borderColor: colors.sentinel.cardBorder,
-    marginBottom: spacing.lg,
-  },
-  partGrid: {
-    gap: spacing.sm,
-    marginBottom: spacing.lg,
-  },
-  partCard: {
-    backgroundColor: colors.sentinel.cardBackground,
-    borderRadius: borderRadius.lg,
-    paddingVertical: spacing.sm,
-    paddingHorizontal: spacing.md,
-    borderWidth: 1,
-    borderColor: colors.sentinel.cardBorder,
-  },
-  partCardStored: {
-    borderColor: colors.sentinel.primary,
-  },
-  partLabel: {
-    fontSize: typography.fontSize.xs,
-    color: colors.sentinel.textSecondary,
-    letterSpacing: typography.letterSpacing.wide,
-    marginBottom: 4,
-    fontWeight: '600',
-  },
-  partValue: {
-    fontSize: typography.fontSize.md,
-    color: colors.sentinel.text,
-    fontFamily: typography.fontFamily.mono,
-    fontWeight: '700',
-    marginBottom: 2,
-  },
-  partHint: {
-    fontSize: typography.fontSize.xs,
-    color: colors.sentinel.textSecondary,
-  },
-  mnemonicBlockText: {
-    fontSize: typography.fontSize.sm,
-    color: colors.sentinel.text,
-    fontFamily: typography.fontFamily.mono,
-    fontWeight: '600',
-    lineHeight: 22,
-    textAlign: 'center',
-  },
-  mnemonicPrimaryButton: {
-    backgroundColor: colors.sentinel.primary,
-    paddingVertical: spacing.sm,
-    borderRadius: borderRadius.full,
-    alignItems: 'center',
-    marginBottom: spacing.sm,
-  },
-  mnemonicButtonDisabled: {
-    opacity: 0.6,
-  },
-  mnemonicPrimaryText: {
-    color: colors.nautical.cream,
-    fontWeight: '700',
-    letterSpacing: typography.letterSpacing.wide,
-  },
-  mnemonicSecondaryButton: {
-    backgroundColor: 'transparent',
-    paddingVertical: spacing.sm,
-    borderRadius: borderRadius.full,
-    alignItems: 'center',
-    borderWidth: 1,
-    borderColor: colors.sentinel.cardBorder,
-  },
-  mnemonicSecondaryText: {
-    color: colors.sentinel.text,
-    fontWeight: '700',
-    letterSpacing: typography.letterSpacing.wide,
-  },
-  emailForm: {
-    marginTop: spacing.sm,
-  },
-  emailInput: {
-    height: 44,
-    borderRadius: borderRadius.full,
-    borderWidth: 1,
-    borderColor: colors.sentinel.cardBorder,
-    paddingHorizontal: spacing.md,
-    color: colors.sentinel.text,
-    fontSize: typography.fontSize.sm,
-    backgroundColor: 'rgba(255, 255, 255, 0.02)',
-    marginBottom: spacing.sm,
-  },
-  emailSendButton: {
-    backgroundColor: colors.nautical.teal,
-    paddingVertical: spacing.sm,
-    borderRadius: borderRadius.full,
-    alignItems: 'center',
-  },
-  emailSendText: {
-    color: colors.nautical.cream,
-    fontWeight: '700',
-    letterSpacing: typography.letterSpacing.wide,
-  },
 });

src/services/ai.service.ts

@@ -12,6 +12,8 @@ import {
   getApiHeaders,
   logApiDebug,
 } from '../config';
+import { AIRole } from '../types';
+import { trimInternalMessages } from '../utils/token_utils';
 
 // =============================================================================
 // Type Definitions
@@ -143,13 +145,14 @@ export const aiService = {
    * Simple helper for single message chat
    * @param content - User message content
    * @param token - JWT token for authentication
+   * @param systemPrompt - Optional custom system prompt
    * @returns AI response text
    */
-  async sendMessage(content: string, token?: string): Promise<string> {
+  async sendMessage(content: string, token?: string, systemPrompt?: string): Promise<string> {
     const messages: AIMessage[] = [
       {
         role: 'system',
-        content: AI_CONFIG.DEFAULT_SYSTEM_PROMPT,
+        content: systemPrompt || AI_CONFIG.DEFAULT_SYSTEM_PROMPT,
       },
       {
         role: 'user',
@@ -240,4 +243,86 @@ export const aiService = {
       throw error;
     }
   },
+
+  /**
+   * Summarize a chat conversation
+   * @param messages - Array of chat messages
+   * @param token - JWT token for authentication
+   * @returns AI summary text
+   */
+  async summarizeChat(messages: AIMessage[], token?: string): Promise<string> {
+    if (NO_BACKEND_MODE) {
+      logApiDebug('AI Summary', 'Using mock mode');
+      return new Promise((resolve) => {
+        setTimeout(() => {
+          resolve('This is a mock summary of your conversation. You discussed various topics including AI integration and UI design. The main conclusion was to proceed with the proposed implementation plan.');
+        }, AI_CONFIG.MOCK_RESPONSE_DELAY);
+      });
+    }
+
+    // Enforce token limit (10,000 tokens)
+    const trimmedMessages = trimInternalMessages(messages);
+
+    const historicalMessages = trimmedMessages.map(msg => ({
+      role: msg.role,
+      content: msg.content,
+    }));
+
+    const summaryPrompt: AIMessage = {
+      role: 'user',
+      content: 'Please provide a concise summary of the conversation above in English. Focus on the main topics discussed and any key conclusions or actions mentioned.',
+    };
+
+    const response = await this.chat([...historicalMessages, summaryPrompt], token);
+    return response.choices[0]?.message?.content || 'No summary generated';
+  },
+
+  /**
+   * Fetch available AI roles from backend
+   * @param token - Optional JWT token for authentication
+   * @returns Array of AI roles
+   */
+  async getAIRoles(token?: string): Promise<AIRole[]> {
+    if (NO_BACKEND_MODE) {
+      logApiDebug('AI Roles', 'Using mock roles');
+      return [...AI_CONFIG.ROLES];
+    }
+
+    if (!token) {
+      console.warn('[AI Service] getAIRoles called without token, falling back to static roles');
+      return [...AI_CONFIG.ROLES];
+    }
+
+    const url = buildApiUrl(API_ENDPOINTS.AI.GET_ROLES);
+    const headers = getApiHeaders(token);
+
+    logApiDebug('AI Roles Request', {
+      url,
+      hasToken: !!token,
+      headers: {
+        ...headers,
+        Authorization: headers.Authorization ? `${headers.Authorization.substring(0, 15)}...` : 'MISSING'
+      }
+    });
+
+    try {
+      const response = await fetch(url, {
+        method: 'GET',
+        headers,
+      });
+
+      if (!response.ok) {
+        console.error(`[AI Service] Failed to fetch AI roles: ${response.status}. Falling back to static roles.`);
+        return [...AI_CONFIG.ROLES];
+      }
+
+      const data = await response.json();
+      logApiDebug('AI Roles Success', { count: data.length });
+      return data;
+    } catch (error) {
+      console.error('[AI Service] Fetch AI roles error:', error);
+      // Fallback to config roles if API fails for better UX
+      return [...AI_CONFIG.ROLES];
+    }
+  },
 };

src/services/assets.service.ts

@@ -23,6 +23,7 @@ export interface Asset {
   author_id: number;
   private_key_shard: string;
   content_outer_encrypted: string;
+  heir_email?: string;
 }
 
 export interface AssetCreate {
@@ -45,7 +46,7 @@ export interface AssetClaimResponse {
 
 export interface AssetAssign {
   asset_id: number;
-  heir_name: string;
+  heir_email: string;
 }
 
 // =============================================================================
@@ -59,6 +60,7 @@ const MOCK_ASSETS: Asset[] = [
     author_id: MOCK_CONFIG.USER.id,
     private_key_shard: 'mock_shard_1',
     content_outer_encrypted: 'mock_encrypted_content_1',
+    heir_email: 'heir@example.com',
   },
   {
     id: 2,
@@ -142,11 +144,16 @@ export const assetsService = {
         body: JSON.stringify(asset),
       });
 
-      logApiDebug('Create Asset Response Status', response.status);
+      const responseStatus = response.status;
+      logApiDebug('Create Asset Response Status', responseStatus);
 
       if (!response.ok) {
         const errorData = await response.json().catch(() => ({}));
-        throw new Error(errorData.detail || 'Failed to create asset');
+        const detail = errorData.detail || 'Failed to create asset';
+        const message = responseStatus === 401 ? `Unauthorized (401): ${detail}` : detail;
+        const err = new Error(message) as Error & { status?: number };
+        err.status = responseStatus;
+        throw err;
       }
 
       return await response.json();
@@ -212,7 +219,7 @@ export const assetsService = {
       logApiDebug('Assign Asset', 'Using mock mode');
       return new Promise((resolve) => {
         setTimeout(() => {
-          resolve({ message: `Asset assigned to ${assignment.heir_name}` });
+          resolve({ message: `Asset assigned to ${assignment.heir_email}` });
         }, MOCK_CONFIG.RESPONSE_DELAY);
       });
     }
@@ -240,4 +247,44 @@ export const assetsService = {
       throw error;
     }
   },
+
+  /**
+   * Delete an asset
+   * @param assetId - ID of the asset to delete
+   * @param token - JWT token for authentication
+   * @returns Success message
+   */
+  async deleteAsset(assetId: number, token: string): Promise<{ message: string }> {
+    if (NO_BACKEND_MODE) {
+      logApiDebug('Delete Asset', `Using mock mode for ID: ${assetId}`);
+      return new Promise((resolve) => {
+        setTimeout(() => {
+          resolve({ message: 'Asset deleted successfully' });
+        }, MOCK_CONFIG.RESPONSE_DELAY);
+      });
+    }
+
+    const url = buildApiUrl(API_ENDPOINTS.ASSETS.DELETE);
+    logApiDebug('Delete Asset URL', url);
+
+    try {
+      const response = await fetch(url, {
+        method: 'POST',
+        headers: getApiHeaders(token),
+        body: JSON.stringify({ asset_id: assetId }),
+      });
+
+      logApiDebug('Delete Asset Response Status', response.status);
+
+      if (!response.ok) {
+        const errorData = await response.json().catch(() => ({}));
+        throw new Error(errorData.detail || 'Failed to delete asset');
+      }
+
+      return await response.json();
+    } catch (error) {
+      console.error('Delete asset error:', error);
+      throw error;
+    }
+  },
 };

src/services/index.ts

@@ -23,3 +23,9 @@ export {
   type DeclareGualeRequest, 
   type DeclareGualeResponse 
 } from './admin.service';
+export {
+  createVaultPayload,
+  createAssetPayload,
+  type CreateVaultPayloadResult,
+  type CreateAssetPayloadResult,
+} from './vault.service';

src/services/langgraph.service.ts

@@ -0,0 +1,96 @@
+/**
+ * LangGraph Service
+ * 
+ * Implements AI chat logic using LangGraph.js for state management
+ * and context handling.
+ */
+
+import { StateGraph, START, END, Annotation } from "@langchain/langgraph";
+import { BaseMessage, HumanMessage, AIMessage, SystemMessage } from "@langchain/core/messages";
+import { aiService } from "./ai.service";
+import { trimLangChainMessages } from "../utils/token_utils";
+
+// =============================================================================
+// Settings
+// =============================================================================
+
+/**
+ * Define the State using Annotation (Standard for latest LangGraph.js)
+ */
+const GraphAnnotation = Annotation.Root({
+    messages: Annotation<BaseMessage[]>({
+        reducer: (x, y) => x.concat(y),
+        default: () => [],
+    }),
+});
+
+// =============================================================================
+// Graph Definition
+// =============================================================================
+
+/**
+ * The main node that calls our existing AI API
+ */
+async function callModel(state: typeof GraphAnnotation.State, config: any) {
+    const { messages } = state;
+    const { token } = config.configurable || {};
+
+    // 1. Trim messages to stay under token limit
+    const trimmedMessages = trimLangChainMessages(messages);
+
+    // 2. Convert LangChain messages to our internal AIMessage format for the API
+    const apiMessages = trimmedMessages.map(m => {
+        let role: 'system' | 'user' | 'assistant' = 'user';
+        const type = (m as any)._getType?.() || (m instanceof SystemMessage ? 'system' : m instanceof HumanMessage ? 'human' : m instanceof AIMessage ? 'ai' : 'user');
+
+        if (type === 'system') role = 'system';
+        else if (type === 'human') role = 'user';
+        else if (type === 'ai') role = 'assistant';
+
+        return {
+            role,
+            content: m.content.toString()
+        };
+    });
+
+    // 3. Call the proxy service
+    const response = await aiService.chat(apiMessages, token);
+    const content = response.choices[0]?.message?.content || "No response generated";
+
+    // 4. Return the new message to satisfy the Graph (it will be appended due to reducer)
+    return {
+        messages: [new AIMessage(content)]
+    };
+}
+
+// =============================================================================
+// Service Export
+// =============================================================================
+
+export const langGraphService = {
+    /**
+     * Run the chat graph with history
+     */
+    async execute(
+        currentMessages: BaseMessage[],
+        userToken: string,
+    ): Promise<string> {
+        // Define the graph
+        const workflow = new StateGraph(GraphAnnotation)
+            .addNode("agent", callModel)
+            .addEdge(START, "agent")
+            .addEdge("agent", END);
+
+        const app = workflow.compile();
+
+        // Execute the graph
+        const result = await app.invoke(
+            { messages: currentMessages },
+            { configurable: { token: userToken } }
+        );
+
+        // Return the content of the last message (the AI response)
+        const lastMsg = result.messages[result.messages.length - 1];
+        return lastMsg.content.toString();
+    }
+};

src/services/storage.service.ts

@@ -0,0 +1,147 @@
+/**
+ * Storage Service
+ * 
+ * Handles local persistence of chat history and active conversations
+ * using AsyncStorage with user-specific isolation.
+ */
+
+import AsyncStorage from '@react-native-async-storage/async-storage';
+
+// =============================================================================
+// Constants
+// =============================================================================
+
+const STORAGE_KEYS = {
+    CHAT_HISTORY: '@sentinel:chat_history',
+    CURRENT_MESSAGES: '@sentinel:current_messages',
+    ASSET_BACKUP: '@sentinel:asset_backup',
+} as const;
+
+// =============================================================================
+// Service Implementation
+// =============================================================================
+
+export const storageService = {
+    /**
+     * Get user-specific storage key
+     */
+    getUserKey(baseKey: string, userId: string | number): string {
+        return `${baseKey}:user_${userId}`;
+    },
+
+    /**
+     * Save the complete list of chat sessions to local storage for a specific user
+     */
+    async saveChatHistory(history: any[], userId: string | number): Promise<void> {
+        try {
+            const jsonValue = JSON.stringify(history);
+            const key = this.getUserKey(STORAGE_KEYS.CHAT_HISTORY, userId);
+            await AsyncStorage.setItem(key, jsonValue);
+            console.log(`[Storage] Saved chat history for user ${userId}:`, history.length, 'sessions');
+        } catch (e) {
+            console.error('Error saving chat history:', e);
+        }
+    },
+
+    /**
+     * Load the list of chat sessions from local storage for a specific user
+     */
+    async getChatHistory(userId: string | number): Promise<any[]> {
+        try {
+            const key = this.getUserKey(STORAGE_KEYS.CHAT_HISTORY, userId);
+            const jsonValue = await AsyncStorage.getItem(key);
+            const result = jsonValue != null ? JSON.parse(jsonValue) : [];
+            console.log(`[Storage] Loaded chat history for user ${userId}:`, result.length, 'sessions');
+            return result;
+        } catch (e) {
+            console.error('Error getting chat history:', e);
+            return [];
+        }
+    },
+
+    /**
+   * Save the current active conversation messages for a specific role and user
+   */
+    async saveCurrentChat(roleId: string, messages: any[], userId: string | number): Promise<void> {
+        try {
+            const jsonValue = JSON.stringify(messages);
+            const key = `${this.getUserKey(STORAGE_KEYS.CURRENT_MESSAGES, userId)}:${roleId}`;
+            await AsyncStorage.setItem(key, jsonValue);
+            console.log(`[Storage] Saved current chat for user ${userId}, role ${roleId}:`, messages.length, 'messages');
+        } catch (e) {
+            console.error(`Error saving current chat for role ${roleId}:`, e);
+        }
+    },
+
+    /**
+     * Load the current active conversation messages for a specific role and user
+     */
+    async getCurrentChat(roleId: string, userId: string | number): Promise<any[]> {
+        try {
+            const key = `${this.getUserKey(STORAGE_KEYS.CURRENT_MESSAGES, userId)}:${roleId}`;
+            const jsonValue = await AsyncStorage.getItem(key);
+            const result = jsonValue != null ? JSON.parse(jsonValue) : [];
+            console.log(`[Storage] Loaded current chat for user ${userId}, role ${roleId}:`, result.length, 'messages');
+            return result;
+        } catch (e) {
+            console.error(`Error getting current chat for role ${roleId}:`, e);
+            return [];
+        }
+    },
+
+    /**
+     * Clear all stored chat data for a specific user
+     */
+    async clearUserData(userId: string | number): Promise<void> {
+        try {
+            const keys = await AsyncStorage.getAllKeys();
+            const userPrefix = `:user_${userId}`;
+            const userKeys = keys.filter(key => key.includes(userPrefix));
+            await AsyncStorage.multiRemove(userKeys);
+            console.log(`[Storage] Cleared all data for user ${userId}:`, userKeys.length, 'keys removed');
+        } catch (e) {
+            console.error('Error clearing user data:', e);
+        }
+    },
+
+    /**
+     * Clear all stored chat data (all users)
+     */
+    async clearAllData(): Promise<void> {
+        try {
+            const keys = await AsyncStorage.getAllKeys();
+            const sentinelKeys = keys.filter(key => key.startsWith('@sentinel:'));
+            await AsyncStorage.multiRemove(sentinelKeys);
+            console.log('[Storage] Cleared all data:', sentinelKeys.length, 'keys removed');
+        } catch (e) {
+            console.error('Error clearing storage data:', e);
+        }
+    },
+
+    /**
+     * Save the plaintext backup of an asset locally
+     */
+    async saveAssetBackup(assetId: number, content: string, userId: string | number): Promise<void> {
+        try {
+            const key = `${this.getUserKey(STORAGE_KEYS.ASSET_BACKUP, userId)}:${assetId}`;
+            await AsyncStorage.setItem(key, content);
+            console.log(`[Storage] Saved asset backup for user ${userId}, asset ${assetId}`);
+        } catch (e) {
+            console.error(`Error saving asset backup for asset ${assetId}:`, e);
+        }
+    },
+
+    /**
+     * Retrieve the plaintext backup of an asset locally
+     */
+    async getAssetBackup(assetId: number, userId: string | number): Promise<string | null> {
+        try {
+            const key = `${this.getUserKey(STORAGE_KEYS.ASSET_BACKUP, userId)}:${assetId}`;
+            return await AsyncStorage.getItem(key);
+        } catch (e) {
+            console.error(`Error getting asset backup for asset ${assetId}:`, e);
+            return null;
+        }
+    }
+};
+

src/services/vault.service.ts

@@ -0,0 +1,81 @@
+/**
+ * Vault Service: 为 /assets/create 生成 private_key_shard 与 content_inner_encrypted
+ *
+ * 流程（与后端 test_scenario / SentinelVault 一致）：
+ * 1. 用 SSS 生成助记词并分片 → 选一个分片作为 private_key_shard（存后端，继承时返回）
+ * 2. 用助记词派生 AES 密钥，对明文做 AES-GCM 加密 → content_inner_encrypted（hex 字符串）
+ *
+ * 使用方式：在任意页面调用 createVaultPayload(plaintext, wordList)，得到可直接传给 assetsService.createAsset 的字段。
+ */
+
+import {
+  generateVaultKeys,
+  serializeShare,
+  type SSSShare,
+  type VaultKeyData,
+} from '../utils/sss';
+import { deriveKey, encryptDataGCM, bytesToHex } from '../utils/vaultCrypto';
+
+export interface CreateVaultPayloadResult {
+  /** 传给后端的 private_key_shard（存一个 SSS 分片的序列化字符串，如云端分片） */
+  private_key_shard: string;
+  /** 传给后端的 content_inner_encrypted（AES-GCM 密文的 hex） */
+  content_inner_encrypted: string;
+  /** 本次生成的助记词（用户需妥善保管，恢复时需任意 2 个分片） */
+  mnemonic: string[];
+  /** 三个分片：device / cloud / heir，可与后端返回的 server_shard 组合恢复助记词 */
+  shares: SSSShare[];
+}
+
+export interface CreateAssetPayloadResult {
+  title: string;
+  type: string;
+  private_key_shard: string;
+  content_inner_encrypted: string;
+}
+
+/**
+ * 生成金库：助记词 + SSS 分片 + 内层加密内容
+ * @param plaintext 要加密的明文（如遗产说明、账号密码等）
+ * @param wordList 助记词词表（与 sss 使用的词表一致）
+ * @param shareIndexForServer 哪个分片存后端，0=device, 1=cloud, 2=heir，默认 1（云端）
+ */
+export async function createVaultPayload(
+  plaintext: string,
+  wordList: readonly string[],
+  shareIndexForServer: 0 | 1 | 2 = 1
+): Promise<CreateVaultPayloadResult> {
+  const { mnemonic, shares }: VaultKeyData = generateVaultKeys(wordList, 12);
+  const mnemonicPhrase = mnemonic.join(' ');
+  const key = await deriveKey(mnemonicPhrase);
+  const encrypted = await encryptDataGCM(key, plaintext);
+  const content_inner_encrypted = bytesToHex(encrypted);
+  const shareForServer = shares[shareIndexForServer];
+  const private_key_shard = serializeShare(shareForServer);
+
+  return {
+    private_key_shard,
+    content_inner_encrypted,
+    mnemonic,
+    shares,
+  };
+}
+
+/**
+ * 生成可直接用于 POST /assets/create 的请求体（含 title / type）
+ */
+export async function createAssetPayload(
+  title: string,
+  plaintext: string,
+  wordList: readonly string[],
+  assetType: string = 'note',
+  shareIndexForServer: 0 | 1 | 2 = 1
+): Promise<CreateAssetPayloadResult> {
+  const vault = await createVaultPayload(plaintext, wordList, shareIndexForServer);
+  return {
+    title,
+    type: assetType,
+    private_key_shard: vault.private_key_shard,
+    content_inner_encrypted: vault.content_inner_encrypted,
+  };
+}

src/types/index.ts

@@ -28,6 +28,8 @@ export interface VaultAsset {
   createdAt: Date;
   updatedAt: Date;
   isEncrypted: boolean;
+  heirEmail?: string;
+  rawData?: any; // For debug logging
 }
 
 // Sentinel Types
@@ -77,6 +79,7 @@ export interface ProtocolInfo {
 export interface User {
   id: number;
   username: string;
+  email?: string;
   public_key: string;
   is_admin: boolean;
   guale: boolean;
@@ -101,3 +104,13 @@ export interface LoginResponse {
   token_type: string;
   user: User;
 }
+
+// AI Types
+export interface AIRole {
+  id: string;
+  name: string;
+  description: string;
+  systemPrompt: string;
+  icon: string;
+  iconFamily: string;
+}

src/utils/async_hooks_mock.ts

@@ -0,0 +1,22 @@
+/**
+ * Mock for Node.js async_hooks
+ * Used to fix LangGraph.js compatibility with React Native
+ */
+
+export class AsyncLocalStorage {
+    disable() { }
+    getStore() {
+        return undefined;
+    }
+    run(store: any, callback: (...args: any[]) => any, ...args: any[]) {
+        return callback(...args);
+    }
+    exit(callback: (...args: any[]) => any, ...args: any[]) {
+        return callback(...args);
+    }
+    enterWith(store: any) { }
+}
+
+export default {
+    AsyncLocalStorage,
+};

src/utils/crypto_core.ts

@@ -0,0 +1,202 @@
+import * as bip39 from 'bip39';
+import * as crypto from 'crypto';
+
+// 定义分片类型：[x坐标, y坐标]
+export type Share = [bigint, bigint];
+
+// 定义生成密钥的返回接口
+export interface VaultKeys {
+    mnemonic: string;
+    entropyHex: string;
+}
+
+export class SentinelKeyEngine {
+    // 使用第 13 个梅森素数 (2^521 - 1)
+    // readonly 确保不会被修改
+    private readonly PRIME: bigint = 2n ** 521n - 1n;
+
+    /**
+     * 1. 生成原始 12 助记词 (Master Key)
+     */
+    public generateVaultKeys(): VaultKeys {
+        // 生成 128 位强度的助记词 (12 个单词)
+        const mnemonic = bip39.generateMnemonic(128);
+
+        // 将助记词转为 16 进制熵 (Hex String)
+        const entropyHex = bip39.mnemonicToEntropy(mnemonic);
+
+        return { mnemonic, entropyHex };
+    }
+
+    public mnemonicToEntropy(mnemonic: string): string {
+        return bip39.mnemonicToEntropy(mnemonic);
+    }
+
+    /**
+     * 2. SSS (3,2) 门限分片逻辑
+     * @param entropyHex - 16进制字符串 (32字符)
+     */
+    public splitToShares(entropyHex: string): Share[] {
+        // 将 Hex 熵转换为 BigInt
+        const secretInt = BigInt('0x' + entropyHex);
+
+        // 生成随机系数 a，范围 [0, PRIME-1]
+        const a = this.secureRandomBigInt(this.PRIME);
+
+        // 定义函数 f(x) = (S + a * x) % PRIME
+        const f = (x: number): bigint => {
+            const xBi = BigInt(x);
+            return (secretInt + a * xBi) % this.PRIME;
+        };
+
+        // 生成 3 个分片: x=1, x=2, x=3
+        const share1: Share = [1n, f(1)]; // 手机分片
+        const share2: Share = [2n, f(2)]; // 云端分片
+        const share3: Share = [3n, f(3)]; // 传承卡分片
+
+        return [share1, share2, share3];
+    }
+
+    /**
+     * 3. 恢复逻辑：拉格朗日插值还原
+     * @param shareA - 第一个分片
+     * @param shareB - 第二个分片
+     */
+    public recoverFromShares(shareA: Share, shareB: Share): string {
+        const [x1, y1] = shareA;
+        const [x2, y2] = shareB;
+
+        // 计算分子: (x2 * y1 - x1 * y2) % PRIME
+        // TS/JS 的 % 运算符对负数返回负数，需修正为正余数
+        let numerator = (x2 * y1 - x1 * y2) % this.PRIME;
+        if (numerator < 0n) numerator += this.PRIME;
+
+        // 计算分母: (x2 - x1)
+        let denominator = (x2 - x1) % this.PRIME;
+        if (denominator < 0n) denominator += this.PRIME;
+
+        // 计算分母的模逆: denominator^-1 mod PRIME
+        // 费马小定理: a^(p-2) = a^-1 (mod p)
+        const invDenominator = this.modPow(denominator, this.PRIME - 2n, this.PRIME);
+
+        // 还原常数项 S
+        const secretInt = (numerator * invDenominator) % this.PRIME;
+
+        // 转回 Hex 字符串
+        let recoveredEntropyHex = secretInt.toString(16);
+
+        // 补齐前导零 (Pad Start)
+        // 128 bit 熵 = 16 字节 = 32 个 Hex 字符
+        // 如果你的熵是 256 bit，这里需要改为 64
+        recoveredEntropyHex = recoveredEntropyHex.padStart(32, '0');
+
+        return bip39.entropyToMnemonic(recoveredEntropyHex);
+    }
+
+    // --- Private Helper Methods ---
+
+    /**
+     * 生成小于 limit 的安全随机 BigInt
+     */
+    private secureRandomBigInt(limit: bigint): bigint {
+        // 计算需要的字节数
+        const bitLength = limit.toString(2).length;
+        const byteLength = Math.ceil(bitLength / 8);
+
+        let randomBi: bigint;
+        do {
+            const buf = crypto.randomBytes(byteLength);
+            randomBi = BigInt('0x' + buf.toString('hex'));
+            // 拒绝采样：确保结果小于 limit
+        } while (randomBi >= limit);
+
+        return randomBi;
+    }
+
+    /**
+     * 模幂运算: (base^exp) % modulus
+     * 用于计算模逆
+     */
+    private modPow(base: bigint, exp: bigint, modulus: bigint): bigint {
+        let result = 1n;
+        base = base % modulus;
+        while (exp > 0n) {
+            if (exp % 2n === 1n) result = (result * base) % modulus;
+            exp = exp >> 1n; // 相当于除以 2
+            base = (base * base) % modulus;
+        }
+        return result;
+    }
+}
+
+export class SentinelVault {
+    private salt: Buffer;
+
+    constructor(salt?: string | Buffer) {
+        // 默认盐值与 Python 版本保持一致
+        this.salt = salt ? Buffer.from(salt) : Buffer.from('Sentinel_Salt_2026');
+    }
+
+    /**
+     * 使用 PBKDF2 将助记词转换为 AES-256 密钥 (32 bytes)
+     */
+    public async deriveKey(mnemonicPhrase: string): Promise<Buffer> {
+        // 1. BIP-39 助记词转种子 (遵循 BIP-39 标准)
+        // Python 的 to_seed 默认返回 64 字节种子
+        const seed = await bip39.mnemonicToSeed(mnemonicPhrase);
+
+        // 2. PBKDF2 派生密钥
+        // 注意：PyCryptodome 的 PBKDF2 默认使用 HMAC-SHA1 (如未指定)
+        // 为了确保与 Python 逻辑严格一致，这里使用 'sha1'
+        return new Promise((resolve, reject) => {
+            crypto.pbkdf2(seed, this.salt, 100000, 32, 'sha1', (err, derivedKey) => {
+                if (err) reject(err);
+                resolve(derivedKey);
+            });
+        });
+    }
+
+    /**
+     * 使用 AES-256-GCM 模式进行加密
+     */
+    public encryptData(key: Buffer, plaintext: string): Buffer {
+        // GCM 模式推荐 nonce 长度，Python 默认通常为 16 字节
+        const iv = crypto.randomBytes(16);
+        const cipher = crypto.createCipheriv('aes-256-gcm', key, iv);
+
+        const ciphertext = Buffer.concat([
+            cipher.update(plaintext, 'utf8'),
+            cipher.final()
+        ]);
+
+        // 获取 GCM 认证标签 (16 bytes)
+        const tag = cipher.getAuthTag();
+
+        // 拼接结果：Nonce + Tag + Ciphertext
+        return Buffer.concat([iv, tag, ciphertext]);
+    }
+
+    /**
+     * AES-256-GCM 解密
+     */
+    public decryptData(key: Buffer, encryptedBlob: Buffer): string {
+        try {
+            // 切片提取组件
+            const iv = encryptedBlob.subarray(0, 16);
+            const tag = encryptedBlob.subarray(16, 32);
+            const ciphertext = encryptedBlob.subarray(32);
+
+            const decipher = crypto.createDecipheriv('aes-256-gcm', key, iv);
+            decipher.setAuthTag(tag);
+
+            const decrypted = Buffer.concat([
+                decipher.update(ciphertext),
+                decipher.final()
+            ]);
+
+            return decrypted.toString('utf8');
+        } catch (error) {
+            return "【解密失败】：密钥错误或数据被篡改";
+        }
+    }
+}

src/utils/crypto_polyfill.ts

@@ -0,0 +1,135 @@
+import * as ExpoCrypto from 'expo-crypto';
+import { Buffer } from 'buffer';
+import { pbkdf2 as noblePbkdf2 } from '@noble/hashes/pbkdf2';
+import { sha1 } from '@noble/hashes/sha1';
+import { sha256 } from '@noble/hashes/sha256';
+import { sha512 } from '@noble/hashes/sha512';
+import { gcm } from '@noble/ciphers/aes';
+
+/**
+ * Node.js Crypto Polyfill for React Native
+ */
+
+export function randomBytes(size: number): Buffer {
+    const bytes = new Uint8Array(size);
+    ExpoCrypto.getRandomValues(bytes);
+    return Buffer.from(bytes);
+}
+
+const hashMap: Record<string, any> = {
+    sha1,
+    sha256,
+    sha512,
+};
+
+export function pbkdf2(
+    password: string | Buffer,
+    salt: string | Buffer,
+    iterations: number,
+    keylen: number,
+    digest: string,
+    callback: (err: Error | null, derivedKey: Buffer) => void
+): void {
+    try {
+        const passwordBytes = typeof password === 'string' ? Buffer.from(password) : password;
+        const saltBytes = typeof salt === 'string' ? Buffer.from(salt) : salt;
+        const hasher = hashMap[digest.toLowerCase()];
+
+        if (!hasher) {
+            throw new Error(`Unsupported digest: ${digest}`);
+        }
+
+        const result = noblePbkdf2(hasher, passwordBytes, saltBytes, {
+            c: iterations,
+            dkLen: keylen,
+        });
+
+        callback(null, Buffer.from(result));
+    } catch (err) {
+        callback(err as Error, Buffer.alloc(0));
+    }
+}
+
+// AES-GCM Implementation
+class Cipher {
+    private key: Uint8Array;
+    private iv: Uint8Array;
+    private authTag: Buffer | null = null;
+    private aesGcm: any;
+    private buffer: Buffer = Buffer.alloc(0);
+
+    constructor(key: Buffer, iv: Buffer) {
+        this.key = new Uint8Array(key);
+        this.iv = new Uint8Array(iv);
+        // @noble/ciphers/aes gcm takes (key, nonce)
+        this.aesGcm = gcm(this.key, this.iv);
+    }
+
+    update(data: string | Buffer, inputEncoding?: string): Buffer {
+        const input = typeof data === 'string' ? Buffer.from(data, inputEncoding as any) : data;
+        this.buffer = Buffer.concat([this.buffer, input]);
+        return Buffer.alloc(0);
+    }
+
+    final(): Buffer {
+        const result = this.aesGcm.encrypt(this.buffer);
+        // @noble/ciphers returns ciphertext + tag (16 bytes)
+        const tag = result.slice(-16);
+        const ciphertext = result.slice(0, -16);
+        this.authTag = Buffer.from(tag);
+        return Buffer.from(ciphertext);
+    }
+
+    getAuthTag(): Buffer {
+        if (!this.authTag) throw new Error('Ciphers: TAG not available before final()');
+        return this.authTag;
+    }
+}
+
+class Decipher {
+    private key: Uint8Array;
+    private iv: Uint8Array;
+    private tag: Uint8Array | null = null;
+    private aesGcm: any;
+    private buffer: Buffer = Buffer.alloc(0);
+
+    constructor(key: Buffer, iv: Buffer) {
+        this.key = new Uint8Array(key);
+        this.iv = new Uint8Array(iv);
+        this.aesGcm = gcm(this.key, this.iv);
+    }
+
+    setAuthTag(tag: Buffer): void {
+        this.tag = new Uint8Array(tag);
+    }
+
+    update(data: Buffer): Buffer {
+        this.buffer = Buffer.concat([this.buffer, data]);
+        return Buffer.alloc(0);
+    }
+
+    final(): Buffer {
+        if (!this.tag) throw new Error('Decipher: Auth tag not set');
+        // @noble/ciphers expects ciphertext then tag
+        const full = new Uint8Array(this.buffer.length + this.tag.length);
+        full.set(this.buffer);
+        full.set(this.tag, this.buffer.length);
+
+        const decrypted = this.aesGcm.decrypt(full);
+        return Buffer.from(decrypted);
+    }
+}
+
+export function createCipheriv(algorithm: string, key: Buffer, iv: Buffer): Cipher {
+    if (algorithm !== 'aes-256-gcm') {
+        throw new Error(`Polyfill only supports aes-256-gcm, got ${algorithm}`);
+    }
+    return new Cipher(key, iv);
+}
+
+export function createDecipheriv(algorithm: string, key: Buffer, iv: Buffer): Decipher {
+    if (algorithm !== 'aes-256-gcm') {
+        throw new Error(`Polyfill only supports aes-256-gcm, got ${algorithm}`);
+    }
+    return new Decipher(key, iv);
+}

src/utils/index.ts

@@ -3,3 +3,4 @@
  */
 
 export * from './sss';
+export * from './vaultAssets';

src/utils/sss.ts

@@ -5,7 +5,12 @@
  * - Secret is split into 3 shares
  * - Any 2 shares can recover the original secret
  *
- * Based on the Sentinel crypto_core_demo Python implementation.
+ * Correspondence with crypto_core_demo (Python):
+ * - sp_trust_sharding.py: split_to_shares(), recover_from_shares()
+ * - Same algorithm: f(x) = secret + a*x (mod P), Lagrange interpolation
+ * - Difference: entropy conversion. Python uses BIP-39 (mnemonic.to_entropy);
+ *   we use custom word list index-based encoding for compatibility with
+ *   existing MNEMONIC_WORDS. SSS split/recover logic is identical.
  */
 
 // Use a large prime for the finite field

src/utils/token_utils.ts

@@ -0,0 +1,76 @@
+/**
+ * Token Utilities
+ * 
+ * Shared logic for trimming messages to stay within token limits.
+ */
+
+import { BaseMessage, SystemMessage } from "@langchain/core/messages";
+import { AIMessage as ServiceAIMessage } from "../services/ai.service";
+
+export const TOKEN_LIMIT = 10000;
+const CHARS_PER_TOKEN = 3; // Conservative estimate: 1 token ≈ 3 chars
+export const MAX_CHARS = TOKEN_LIMIT * CHARS_PER_TOKEN;
+
+/**
+ * Trims LangChain messages to fit within token limit
+ */
+export function trimLangChainMessages(messages: BaseMessage[]): BaseMessage[] {
+    let totalLength = 0;
+    const trimmed: BaseMessage[] = [];
+
+    // Always keep the system message if it's at the start
+    let systemMsg: BaseMessage | null = null;
+    if (messages.length > 0 && (messages[0] instanceof SystemMessage || (messages[0] as any)._getType?.() === 'system')) {
+        systemMsg = messages[0];
+        totalLength += systemMsg.content.toString().length;
+    }
+
+    // Iterate backwards and add messages until we hit the char limit
+    for (let i = messages.length - 1; i >= (systemMsg ? 1 : 0); i--) {
+        const msg = messages[i];
+        const len = msg.content.toString().length;
+
+        if (totalLength + len > MAX_CHARS) break;
+
+        trimmed.unshift(msg);
+        totalLength += len;
+    }
+
+    if (systemMsg) {
+        trimmed.unshift(systemMsg);
+    }
+
+    return trimmed;
+}
+
+/**
+ * Trims internal AIMessage format messages to fit within token limit
+ */
+export function trimInternalMessages(messages: ServiceAIMessage[]): ServiceAIMessage[] {
+    let totalLength = 0;
+    const trimmed: ServiceAIMessage[] = [];
+
+    // Always keep the system message if it's at the start
+    let systemMsg: ServiceAIMessage | null = null;
+    if (messages.length > 0 && messages[0].role === 'system') {
+        systemMsg = messages[0];
+        totalLength += systemMsg.content.length;
+    }
+
+    // Iterate backwards and add messages until we hit the char limit
+    for (let i = messages.length - 1; i >= (systemMsg ? 1 : 0); i--) {
+        const msg = messages[i];
+        const len = msg.content.length;
+
+        if (totalLength + len > MAX_CHARS) break;
+
+        trimmed.unshift(msg);
+        totalLength += len;
+    }
+
+    if (systemMsg) {
+        trimmed.unshift(systemMsg);
+    }
+
+    return trimmed;
+}

src/utils/vaultAssets.ts

@@ -0,0 +1,71 @@
+/**
+ * Vault assets: API ↔ UI mapping and initial mock data.
+ * Used by useVaultAssets and VaultScreen for /assets/get and /assets/create flows.
+ */
+
+import type { VaultAsset, VaultAssetType } from '../types';
+
+// -----------------------------------------------------------------------------
+// Types
+// -----------------------------------------------------------------------------
+
+/** Shape returned by GET /assets/get (backend AssetOut) */
+export interface ApiAsset {
+  id: number;
+  title: string;
+  type?: string;
+  author_id?: number;
+  private_key_shard?: string;
+  content_outer_encrypted?: string;
+  created_at?: string;
+  updated_at?: string;
+  heir_id?: number;
+  heir_email?: string;
+}
+
+// -----------------------------------------------------------------------------
+// Constants
+// -----------------------------------------------------------------------------
+
+export const VAULT_ASSET_TYPES: VaultAssetType[] = [
+  'game_account',
+  'private_key',
+  'document',
+  'photo',
+  'will',
+  'custom',
+];
+
+export const initialVaultAssets: VaultAsset[] = [];
+
+// -----------------------------------------------------------------------------
+// Mapping
+// -----------------------------------------------------------------------------
+
+/**
+ * Map backend API asset to VaultAsset for UI.
+ */
+export function mapApiAssetToVaultAsset(api: ApiAsset): VaultAsset {
+  const type: VaultAssetType =
+    api.type && VAULT_ASSET_TYPES.includes(api.type as VaultAssetType)
+      ? (api.type as VaultAssetType)
+      : 'custom';
+  return {
+    id: String(api.id),
+    type,
+    label: api.title,
+    createdAt: api.created_at ? new Date(api.created_at) : new Date(),
+    updatedAt: api.updated_at ? new Date(api.updated_at) : new Date(),
+    isEncrypted: true,
+    heirEmail: api.heir_email,
+    rawData: api,
+  };
+}
+
+/**
+ * Map array of API assets to VaultAsset[].
+ */
+export function mapApiAssetsToVaultAssets(apiList: ApiAsset[]): VaultAsset[] {
+  return apiList.map(mapApiAssetToVaultAsset);
+}
+

src/utils/vaultCrypto.ts

@@ -0,0 +1,107 @@
+/**
+ * Vault crypto: PBKDF2 key derivation + AES-256-GCM encrypt/decrypt.
+ * Matches backend SentinelVault semantics (PBKDF2 from mnemonic, AES-GCM).
+ * Uses Web Crypto API (crypto.subtle). Requires secure context / React Native polyfill if needed.
+ */
+
+const SALT = new TextEncoder().encode('Sentinel_Salt_2026');
+const PBKDF2_ITERATIONS = 100000;
+const AES_KEY_LEN = 256;
+const GCM_IV_LEN = 16;
+const GCM_TAG_LEN = 16;
+
+function getCrypto(): Crypto {
+  if (typeof crypto !== 'undefined' && crypto.subtle) return crypto;
+  throw new Error('vaultCrypto: crypto.subtle not available');
+}
+
+/**
+ * Derive a 32-byte AES key from mnemonic phrase (space-separated words).
+ */
+export async function deriveKey(mnemonicPhrase: string, salt: Uint8Array = SALT): Promise<ArrayBuffer> {
+  const crypto = getCrypto();
+  const keyMaterial = await crypto.subtle.importKey(
+    'raw',
+    new TextEncoder().encode(mnemonicPhrase),
+    'PBKDF2',
+    false,
+    ['deriveBits']
+  );
+  const saltBuf = salt.buffer.slice(salt.byteOffset, salt.byteOffset + salt.byteLength) as ArrayBuffer;
+  const bits = await crypto.subtle.deriveBits(
+    {
+      name: 'PBKDF2',
+      salt: saltBuf,
+      iterations: PBKDF2_ITERATIONS,
+      hash: 'SHA-256',
+    },
+    keyMaterial,
+    AES_KEY_LEN
+  );
+  return bits;
+}
+
+/**
+ * Encrypt plaintext with AES-256-GCM. Returns nonce(16) + tag(16) + ciphertext (matches Python SentinelVault).
+ */
+export async function encryptDataGCM(key: ArrayBuffer, plaintext: string): Promise<Uint8Array> {
+  const crypto = getCrypto();
+  const iv = crypto.getRandomValues(new Uint8Array(GCM_IV_LEN));
+  const cryptoKey = await crypto.subtle.importKey(
+    'raw',
+    key,
+    { name: 'AES-GCM' },
+    false,
+    ['encrypt']
+  );
+  const encoded = new TextEncoder().encode(plaintext);
+  const ciphertextWithTag = await crypto.subtle.encrypt(
+    { name: 'AES-GCM', iv, tagLength: GCM_TAG_LEN * 8 },
+    cryptoKey,
+    encoded
+  );
+  const out = new Uint8Array(iv.length + ciphertextWithTag.byteLength);
+  out.set(iv, 0);
+  out.set(new Uint8Array(ciphertextWithTag), iv.length);
+  return out;
+}
+
+/**
+ * Decrypt blob from encryptDataGCM (nonce(16) + ciphertext+tag).
+ */
+export async function decryptDataGCM(key: ArrayBuffer, blob: Uint8Array): Promise<string> {
+  const crypto = getCrypto();
+  const iv = blob.subarray(0, GCM_IV_LEN);
+  const ciphertextWithTag = blob.subarray(GCM_IV_LEN);
+  const ivBuf = iv.buffer.slice(iv.byteOffset, iv.byteOffset + iv.byteLength) as ArrayBuffer;
+  const ctBuf = ciphertextWithTag.buffer.slice(
+    ciphertextWithTag.byteOffset,
+    ciphertextWithTag.byteOffset + ciphertextWithTag.byteLength
+  ) as ArrayBuffer;
+  const cryptoKey = await crypto.subtle.importKey(
+    'raw',
+    key,
+    { name: 'AES-GCM' },
+    false,
+    ['decrypt']
+  );
+  const dec = await crypto.subtle.decrypt(
+    { name: 'AES-GCM', iv: ivBuf, tagLength: GCM_TAG_LEN * 8 },
+    cryptoKey,
+    ctBuf
+  );
+  return new TextDecoder().decode(dec);
+}
+
+export function bytesToHex(bytes: Uint8Array): string {
+  return Array.from(bytes)
+    .map((b) => b.toString(16).padStart(2, '0'))
+    .join('');
+}
+
+export function hexToBytes(hex: string): Uint8Array {
+  const len = hex.length / 2;
+  const out = new Uint8Array(len);
+  for (let i = 0; i < len; i++) out[i] = parseInt(hex.slice(i * 2, i * 2 + 2), 16);
+  return out;
+}