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/escalade/dist/index.js

@@ -0,0 +1,22 @@
+const { dirname, resolve } = require('path');
+const { readdir, stat } = require('fs');
+const { promisify } = require('util');
+
+const toStats = promisify(stat);
+const toRead = promisify(readdir);
+
+module.exports = async function (start, callback) {
+	let dir = resolve('.', start);
+	let tmp, stats = await toStats(dir);
+
+	if (!stats.isDirectory()) {
+		dir = dirname(dir);
+	}
+
+	while (true) {
+		tmp = await callback(dir, await toRead(dir));
+		if (tmp) return resolve(dir, tmp);
+		dir = dirname(tmp = dir);
+		if (tmp === dir) break;
+	}
+}

smart-app-city/frontend/node_modules/escalade/dist/index.mjs

@@ -0,0 +1,22 @@
+import { dirname, resolve } from 'path';
+import { readdir, stat } from 'fs';
+import { promisify } from 'util';
+
+const toStats = promisify(stat);
+const toRead = promisify(readdir);
+
+export default async function (start, callback) {
+	let dir = resolve('.', start);
+	let tmp, stats = await toStats(dir);
+
+	if (!stats.isDirectory()) {
+		dir = dirname(dir);
+	}
+
+	while (true) {
+		tmp = await callback(dir, await toRead(dir));
+		if (tmp) return resolve(dir, tmp);
+		dir = dirname(tmp = dir);
+		if (tmp === dir) break;
+	}
+}