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/@react-native/dev-middleware/README.md

@@ -0,0 +1,89 @@
+# @react-native/dev-middleware
+
+![npm package](https://img.shields.io/npm/v/@react-native/dev-middleware?color=brightgreen&label=npm%20package)
+
+Dev server middleware supporting core React Native development features. This package is preconfigured in all React Native projects.
+
+## Usage
+
+Middleware can be attached to a dev server (e.g. [Metro](https://facebook.github.io/metro/docs/getting-started)) using the `createDevMiddleware` API.
+
+```js
+import { createDevMiddleware } from '@react-native/dev-middleware';
+
+function myDevServerImpl(args) {
+  ...
+
+  const {middleware, websocketEndpoints} = createDevMiddleware({
+    projectRoot: metroConfig.projectRoot,
+    serverBaseUrl: `http://${args.host}:${args.port}`,
+    logger,
+  });
+
+  await Metro.runServer(metroConfig, {
+    host: args.host,
+    ...,
+    unstable_extraMiddleware: [
+      middleware,
+      // Optionally extend with additional HTTP middleware
+    ],
+    websocketEndpoints: {
+      ...websocketEndpoints,
+      // Optionally extend with additional WebSocket endpoints
+    },
+  });
+}
+```
+
+## Included middleware
+
+`@react-native/dev-middleware` is designed for integrators such as [`@expo/dev-server`](https://www.npmjs.com/package/@expo/dev-server) and [`@react-native/community-cli-plugin`](https://github.com/facebook/react-native/tree/main/packages/community-cli-plugin). It provides a common default implementation for core React Native dev server responsibilities.
+
+We intend to keep this to a narrow set of functionality, based around:
+
+- **Debugging** — The [Chrome DevTools protocol (CDP)](https://chromedevtools.github.io/devtools-protocol/) endpoints supported by React Native, including the Inspector Proxy, which facilitates connections with multiple devices.
+- **Dev actions** — Endpoints implementing core [Dev Menu](https://reactnative.dev/docs/debugging#accessing-the-dev-menu) actions, e.g. reloading the app, opening the debugger frontend.
+
+### HTTP endpoints
+
+<small>`DevMiddlewareAPI.middleware`</small>
+
+These are exposed as a [`connect`](https://www.npmjs.com/package/connect) middleware handler, assignable to `Metro.runServer` or other compatible HTTP servers.
+
+#### GET `/json/list`, `/json` ([CDP](https://chromedevtools.github.io/devtools-protocol/#endpoints))
+
+Returns the list of available WebSocket targets for all connected React Native app sessions.
+
+#### GET `/json/version` ([CDP](https://chromedevtools.github.io/devtools-protocol/#endpoints))
+
+Returns version metadata used by Chrome DevTools.
+
+#### GET `/debugger-frontend`
+
+Subpaths of this endpoint are reserved to serve the JavaScript debugger frontend.
+
+#### POST `/open-debugger`
+
+Open the JavaScript debugger for a given CDP target (direct Hermes debugging).
+
+<details>
+<summary>Example</summary>
+
+    curl -X POST 'http://localhost:8081/open-debugger?appId=com.meta.RNTester'
+</details>
+
+### WebSocket endpoints
+
+<small>`DevMiddlewareAPI.websocketEndpoints`</small>
+
+#### `/inspector/device`
+
+WebSocket handler for registering device connections.
+
+#### `/inspector/debug`
+
+WebSocket handler that proxies CDP messages to/from the corresponding device.
+
+## Contributing
+
+Changes to this package can be made locally and tested against the `rn-tester` app, per the [Contributing guide](https://reactnative.dev/contributing/overview#contributing-code). During development, this package is automatically run from source with no build step.