update flow and auth model

App.tsx

@@ -1,28 +1,54 @@
+/**
+ * App Entry Point
+ * 
+ * Main application component with authentication routing.
+ * Shows loading screen while restoring auth state.
+ */
+
 import React from 'react';
 import { StatusBar } from 'expo-status-bar';
 import { NavigationContainer } from '@react-navigation/native';
 import { GestureHandlerRootView } from 'react-native-gesture-handler';
-import { StyleSheet, View, ActivityIndicator } from 'react-native';
+import { StyleSheet, View, ActivityIndicator, Text } from 'react-native';
 import TabNavigator from './src/navigation/TabNavigator';
 import AuthNavigator from './src/navigation/AuthNavigator';
 import { AuthProvider, useAuth } from './src/context/AuthContext';
 import { colors } from './src/theme/colors';
 
+/**
+ * Loading screen shown while restoring auth state
+ */
+function LoadingScreen() {
+  return (
+    <View style={styles.loadingContainer}>
+      <ActivityIndicator size="large" color={colors.nautical.teal} />
+      <Text style={styles.loadingText}>Loading...</Text>
+    </View>
+  );
+}
+
+/**
+ * Main app content with auth-based routing
+ */
 function AppContent() {
-  const { user } = useAuth();
+  const { user, isInitializing } = useAuth();
+
+  // Show loading screen while restoring auth state
+  if (isInitializing) {
+    return <LoadingScreen />;
+  }
 
   return (
     <NavigationContainer>
       <StatusBar style="auto" />
-      {user ? (
-        <TabNavigator />
-      ) : (
-        <AuthNavigator />
-      )}
+      {user ? <TabNavigator /> : <AuthNavigator />}
     </NavigationContainer>
   );
 }
 
+/**
+ * Root App component
+ */
 export default function App() {
   return (
     <GestureHandlerRootView style={styles.container}>
@@ -42,7 +68,11 @@ const styles = StyleSheet.create({
     flex: 1,
     justifyContent: 'center',
     alignItems: 'center',
-    backgroundColor: colors.sentinel.background,
+    backgroundColor: colors.flow.backgroundGradientStart,
+  },
+  loadingText: {
+    marginTop: 16,
+    fontSize: 16,
+    color: colors.flow.textSecondary,
   },
 });
-