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/fbjs/lib/forEachObject.js.flow

@@ -0,0 +1,40 @@
+/**
+ * Copyright (c) 2013-present, Facebook, Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @providesModule forEachObject
+ * @typechecks
+ */
+'use strict';
+
+var hasOwnProperty = Object.prototype.hasOwnProperty;
+/**
+ * Executes the provided `callback` once for each enumerable own property in the
+ * object. The `callback` is invoked with three arguments:
+ *
+ *  - the property value
+ *  - the property name
+ *  - the object being traversed
+ *
+ * Properties that are added after the call to `forEachObject` will not be
+ * visited by `callback`. If the values of existing properties are changed, the
+ * value passed to `callback` will be the value at the time `forEachObject`
+ * visits them. Properties that are deleted before being visited are not
+ * visited.
+ *
+ * @param {?object} object
+ * @param {function} callback
+ * @param {*} context
+ */
+
+function forEachObject(object, callback, context) {
+  for (var name in object) {
+    if (hasOwnProperty.call(object, name)) {
+      callback.call(context, object[name], name, object);
+    }
+  }
+}
+
+module.exports = forEachObject;