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/nanoid/index.d.ts

@@ -0,0 +1,91 @@
+/**
+ * Generate secure URL-friendly unique ID.
+ *
+ * By default, the ID will have 21 symbols to have a collision probability
+ * similar to UUID v4.
+ *
+ * ```js
+ * import { nanoid } from 'nanoid'
+ * model.id = nanoid() //=> "Uakgb_J5m9g-0JDMbcJqL"
+ * ```
+ *
+ * @param size Size of the ID. The default size is 21.
+ * @returns A random string.
+ */
+export function nanoid(size?: number): string
+
+/**
+ * Generate secure unique ID with custom alphabet.
+ *
+ * Alphabet must contain 256 symbols or less. Otherwise, the generator
+ * will not be secure.
+ *
+ * @param alphabet Alphabet used to generate the ID.
+ * @param defaultSize Size of the ID. The default size is 21.
+ * @returns A random string generator.
+ *
+ * ```js
+ * const { customAlphabet } = require('nanoid')
+ * const nanoid = customAlphabet('0123456789абвгдеё', 5)
+ * nanoid() //=> "8ё56а"
+ * ```
+ */
+export function customAlphabet(
+  alphabet: string,
+  defaultSize?: number
+): (size?: number) => string
+
+/**
+ * Generate unique ID with custom random generator and alphabet.
+ *
+ * Alphabet must contain 256 symbols or less. Otherwise, the generator
+ * will not be secure.
+ *
+ * ```js
+ * import { customRandom } from 'nanoid/format'
+ *
+ * const nanoid = customRandom('abcdef', 5, size => {
+ *   const random = []
+ *   for (let i = 0; i < size; i++) {
+ *     random.push(randomByte())
+ *   }
+ *   return random
+ * })
+ *
+ * nanoid() //=> "fbaef"
+ * ```
+ *
+ * @param alphabet Alphabet used to generate a random string.
+ * @param size Size of the random string.
+ * @param random A random bytes generator.
+ * @returns A random string generator.
+ */
+export function customRandom(
+  alphabet: string,
+  size: number,
+  random: (bytes: number) => Uint8Array
+): () => string
+
+/**
+ * URL safe symbols.
+ *
+ * ```js
+ * import { urlAlphabet } from 'nanoid'
+ * const nanoid = customAlphabet(urlAlphabet, 10)
+ * nanoid() //=> "Uakgb_J5m9"
+ * ```
+ */
+export const urlAlphabet: string
+
+/**
+ * Generate an array of random bytes collected from hardware noise.
+ *
+ * ```js
+ * import { customRandom, random } from 'nanoid'
+ * const nanoid = customRandom("abcdef", 5, random)
+ * ```
+ *
+ * @param bytes Size of the array.
+ * @returns An array of random bytes.
+ */
+export function random(bytes: number): Uint8Array