feat(smart-app): implement complete mobile app MVP

- App.tsx: full navigation (Auth stack + Main tabs with 5 screens)
- Auth: LoginScreen, RegisterScreen, ForgotPasswordScreen
- HomeScreen: dashboard with IoT metrics, weather widget, alerts, quick actions, sensors
- MapScreen: interactive map with layer toggles (6 layers)
- MarketplaceScreen: categories (6), products (5), search
- ChatScreen: AI chat with quick prompts (4), bot responses
- ProfileScreen: user info, stats, menu (9 items), logout
- AlertsScreen: alert list with severity, acknowledge
- SensorsScreen: sensor list with type filters (6 types), search
- ZonesScreen: zone cards with stats
- SettingsScreen: language picker (FR/EN/ES/DE), privacy, about
- Stores: iotStore (sensors, zones, alerts), notificationStore, uiStore + i18n
- Hooks: useSensors, useAlerts, useNotifications, useLocation
- Components: Card, Button, LoadingSpinner, ErrorBoundary, Header
- Services: iotService, notificationService (with axios API client)
- Utils: formatters (temp, AQI, noise, dates), validators (email, password, IBAN)
- Theme: colors.ts with full design system (Blue Ocean palette)
- Ditto: fixed MongoDB connection, new JWT secrets, official gateway image

smart-app-city/frontend/node_modules/expo-asset/build/ExpoAsset.d.ts

@@ -0,0 +1,11 @@
+/**
+ * Downloads the asset from the given URL to a local cache and returns the local URL of the cached
+ * file.
+ *
+ * If there is already a locally cached file and its MD5 hash matches the given `md5Hash` parameter,
+ * if present, the remote asset is not downloaded. The `hash` property is included in Metro's asset
+ * metadata objects when this module's `hashAssetFiles` plugin is used, which is the typical way the
+ * `md5Hash` parameter of this function is provided.
+ */
+export declare function downloadAsync(url: string, md5Hash: string | null, type: string): Promise<string>;
+//# sourceMappingURL=ExpoAsset.d.ts.map