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/es-abstract/helpers/bytesAsInteger.js

@@ -0,0 +1,32 @@
+'use strict';
+
+var GetIntrinsic = require('get-intrinsic');
+
+var $pow = require('math-intrinsics/pow');
+
+var $Number = GetIntrinsic('%Number%');
+var $BigInt = GetIntrinsic('%BigInt%', true);
+
+module.exports = function bytesAsInteger(rawBytes, elementSize, isUnsigned, isBigInt) {
+	var Z = isBigInt ? $BigInt : $Number;
+
+	// this is common to both branches
+	var intValue = Z(0);
+	for (var i = 0; i < rawBytes.length; i++) {
+		intValue += Z(rawBytes[i] * $pow(2, 8 * i));
+	}
+	/*
+	Let intValue be the byte elements of rawBytes concatenated and interpreted as a bit string encoding of an unsigned little-endian binary number.
+	*/
+
+	if (!isUnsigned) { // steps 5-6
+		// Let intValue be the byte elements of rawBytes concatenated and interpreted as a bit string encoding of a binary little-endian 2's complement number of bit length elementSize × 8.
+		var bitLength = elementSize * 8;
+
+		if (rawBytes[elementSize - 1] & 0x80) {
+			intValue -= Z($pow(2, bitLength));
+		}
+	}
+
+	return intValue; // step 7
+};