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/dayjs/esm/plugin/arraySupport/index.d.ts

@@ -0,0 +1,10 @@
+import { PluginFunc } from 'dayjs/esm'
+
+declare module 'dayjs/esm' {
+  interface ConfigTypeMap {
+    arraySupport: [number?, number?, number?, number?, number?, number?, number?]
+  }
+}
+
+declare const plugin: PluginFunc
+export = plugin

smart-app-city/frontend/node_modules/dayjs/esm/plugin/arraySupport/index.js

@@ -0,0 +1,33 @@
+export default (function (o, c, dayjs) {
+  var proto = c.prototype;
+
+  var parseDate = function parseDate(cfg) {
+    var date = cfg.date,
+        utc = cfg.utc;
+
+    if (Array.isArray(date)) {
+      if (utc) {
+        if (!date.length) {
+          return new Date();
+        }
+
+        return new Date(Date.UTC.apply(null, date));
+      }
+
+      if (date.length === 1) {
+        return dayjs(String(date[0])).toDate();
+      }
+
+      return new (Function.prototype.bind.apply(Date, [null].concat(date)))();
+    }
+
+    return date;
+  };
+
+  var oldParse = proto.parse;
+
+  proto.parse = function (cfg) {
+    cfg.date = parseDate.bind(this)(cfg);
+    oldParse.bind(this)(cfg);
+  };
+});