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/template/android/app/src/debug/AndroidManifest.xml

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools">
+
+    <application
+        android:usesCleartextTraffic="true"
+        tools:targetApi="28"
+        tools:ignore="GoogleAppIndexingWarning"/>
+</manifest>

smart-app-city/frontend/node_modules/react-native/template/android/app/src/main/AndroidManifest.xml

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+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+
+    <uses-permission android:name="android.permission.INTERNET" />
+
+    <application
+      android:name=".MainApplication"
+      android:label="@string/app_name"
+      android:icon="@mipmap/ic_launcher"
+      android:roundIcon="@mipmap/ic_launcher_round"
+      android:allowBackup="false"
+      android:theme="@style/AppTheme">
+      <activity
+        android:name=".MainActivity"
+        android:label="@string/app_name"
+        android:configChanges="keyboard|keyboardHidden|orientation|screenLayout|screenSize|smallestScreenSize|uiMode"
+        android:launchMode="singleTask"
+        android:windowSoftInputMode="adjustResize"
+        android:exported="true">
+        <intent-filter>
+            <action android:name="android.intent.action.MAIN" />
+            <category android:name="android.intent.category.LAUNCHER" />
+        </intent-filter>
+      </activity>
+    </application>
+</manifest>

smart-app-city/frontend/node_modules/react-native/template/android/app/src/main/java/com/helloworld/MainActivity.kt

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+package com.helloworld
+
+import com.facebook.react.ReactActivity
+import com.facebook.react.ReactActivityDelegate
+import com.facebook.react.defaults.DefaultNewArchitectureEntryPoint.fabricEnabled
+import com.facebook.react.defaults.DefaultReactActivityDelegate
+
+class MainActivity : ReactActivity() {
+
+  /**
+   * Returns the name of the main component registered from JavaScript. This is used to schedule
+   * rendering of the component.
+   */
+  override fun getMainComponentName(): String = "HelloWorld"
+
+  /**
+   * Returns the instance of the [ReactActivityDelegate]. We use [DefaultReactActivityDelegate]
+   * which allows you to enable New Architecture with a single boolean flags [fabricEnabled]
+   */
+  override fun createReactActivityDelegate(): ReactActivityDelegate =
+      DefaultReactActivityDelegate(this, mainComponentName, fabricEnabled)
+}

smart-app-city/frontend/node_modules/react-native/template/android/app/src/main/java/com/helloworld/MainApplication.kt

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+package com.helloworld
+
+import android.app.Application
+import com.facebook.react.PackageList
+import com.facebook.react.ReactApplication
+import com.facebook.react.ReactHost
+import com.facebook.react.ReactNativeHost
+import com.facebook.react.ReactPackage
+import com.facebook.react.defaults.DefaultNewArchitectureEntryPoint.load
+import com.facebook.react.defaults.DefaultReactHost.getDefaultReactHost
+import com.facebook.react.defaults.DefaultReactNativeHost
+import com.facebook.soloader.SoLoader
+
+class MainApplication : Application(), ReactApplication {
+
+  override val reactNativeHost: ReactNativeHost =
+      object : DefaultReactNativeHost(this) {
+        override fun getPackages(): List<ReactPackage> =
+            PackageList(this).packages.apply {
+              // Packages that cannot be autolinked yet can be added manually here, for example:
+              // add(MyReactNativePackage())
+            }
+
+        override fun getJSMainModuleName(): String = "index"
+
+        override fun getUseDeveloperSupport(): Boolean = BuildConfig.DEBUG
+
+        override val isNewArchEnabled: Boolean = BuildConfig.IS_NEW_ARCHITECTURE_ENABLED
+        override val isHermesEnabled: Boolean = BuildConfig.IS_HERMES_ENABLED
+      }
+
+  override val reactHost: ReactHost
+    get() = getDefaultReactHost(applicationContext, reactNativeHost)
+
+  override fun onCreate() {
+    super.onCreate()
+    SoLoader.init(this, false)
+    if (BuildConfig.IS_NEW_ARCHITECTURE_ENABLED) {
+      // If you opted-in for the New Architecture, we load the native entry point for this app.
+      load()
+    }
+  }
+}

smart-app-city/frontend/node_modules/react-native/template/android/app/src/main/res/drawable/rn_edit_text_material.xml

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+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2014 The Android Open Source Project
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
+<inset xmlns:android="http://schemas.android.com/apk/res/android"
+       android:insetLeft="@dimen/abc_edit_text_inset_horizontal_material"
+       android:insetRight="@dimen/abc_edit_text_inset_horizontal_material"
+       android:insetTop="@dimen/abc_edit_text_inset_top_material"
+       android:insetBottom="@dimen/abc_edit_text_inset_bottom_material"
+       >
+
+    <selector>
+        <!--
+          This file is a copy of abc_edit_text_material (https://bit.ly/3k8fX7I).
+          The item below with state_pressed="false" and state_focused="false" causes a NullPointerException.
+          NullPointerException:tempt to invoke virtual method 'android.graphics.drawable.Drawable android.graphics.drawable.Drawable$ConstantState.newDrawable(android.content.res.Resources)'
+
+          <item android:state_pressed="false" android:state_focused="false" android:drawable="@drawable/abc_textfield_default_mtrl_alpha"/>
+
+          For more info, see https://bit.ly/3CdLStv (react-native/pull/29452) and https://bit.ly/3nxOMoR.
+        -->
+        <item android:state_enabled="false" android:drawable="@drawable/abc_textfield_default_mtrl_alpha"/>
+        <item android:drawable="@drawable/abc_textfield_activated_mtrl_alpha"/>
+    </selector>
+
+</inset>

smart-app-city/frontend/node_modules/react-native/template/android/app/src/main/res/values/strings.xml

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+<resources>
+    <string name="app_name">Hello App Display Name</string>
+</resources>

smart-app-city/frontend/node_modules/react-native/template/android/app/src/main/res/values/styles.xml

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+<resources>
+
+    <!-- Base application theme. -->
+    <style name="AppTheme" parent="Theme.AppCompat.DayNight.NoActionBar">
+        <!-- Customize your theme here. -->
+        <item name="android:editTextBackground">@drawable/rn_edit_text_material</item>
+    </style>
+
+</resources>