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/README.md

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+# Nano ID
+
+<img src="https://ai.github.io/nanoid/logo.svg" align="right"
+     alt="Nano ID logo by Anton Lovchikov" width="180" height="94">
+
+**English** | [Русский](./README.ru.md) | [简体中文](./README.zh-CN.md) | [Bahasa Indonesia](./README.id-ID.md)
+
+A tiny, secure, URL-friendly, unique string ID generator for JavaScript.
+
+> “An amazing level of senseless perfectionism,
+> which is simply impossible not to respect.”
+
+* **Small.** 130 bytes (minified and gzipped). No dependencies.
+  [Size Limit] controls the size.
+* **Fast.** It is 2 times faster than UUID.
+* **Safe.** It uses hardware random generator. Can be used in clusters.
+* **Short IDs.** It uses a larger alphabet than UUID (`A-Za-z0-9_-`).
+  So ID size was reduced from 36 to 21 symbols.
+* **Portable.** Nano ID was ported
+  to [20 programming languages](#other-programming-languages).
+
+```js
+import { nanoid } from 'nanoid'
+model.id = nanoid() //=> "V1StGXR8_Z5jdHi6B-myT"
+```
+
+Supports modern browsers, IE [with Babel], Node.js and React Native.
+
+[online tool]: https://gitpod.io/#https://github.com/ai/nanoid/
+[with Babel]:  https://developer.epages.com/blog/coding/how-to-transpile-node-modules-with-babel-and-webpack-in-a-monorepo/
+[Size Limit]:  https://github.com/ai/size-limit
+
+<a href="https://evilmartians.com/?utm_source=nanoid">
+  <img src="https://evilmartians.com/badges/sponsored-by-evil-martians.svg"
+       alt="Sponsored by Evil Martians" width="236" height="54">
+</a>
+
+## Docs
+Read full docs **[here](https://github.com/ai/nanoid#readme)**.