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/xmlbuilder/lib/XMLStringWriter.js

@@ -0,0 +1,40 @@
+// Generated by CoffeeScript 2.4.1
+(function() {
+  var XMLStringWriter, XMLWriterBase;
+
+  XMLWriterBase = require('./XMLWriterBase');
+
+  // Prints XML nodes as plain text
+  module.exports = XMLStringWriter = class XMLStringWriter extends XMLWriterBase {
+    // Initializes a new instance of `XMLStringWriter`
+
+    // `options.pretty` pretty prints the result
+    // `options.indent` indentation string
+    // `options.newline` newline sequence
+    // `options.offset` a fixed number of indentations to add to every line
+    // `options.allowEmpty` do not self close empty element tags
+    // 'options.dontPrettyTextNodes' if any text is present in node, don't indent or LF
+    // `options.spaceBeforeSlash` add a space before the closing slash of empty elements
+    constructor(options) {
+      super(options);
+    }
+
+    document(doc, options) {
+      var child, i, len, r, ref;
+      options = this.filterOptions(options);
+      r = '';
+      ref = doc.children;
+      for (i = 0, len = ref.length; i < len; i++) {
+        child = ref[i];
+        r += this.writeChildNode(child, options, 0);
+      }
+      // remove trailing newline
+      if (options.pretty && r.slice(-options.newline.length) === options.newline) {
+        r = r.slice(0, -options.newline.length);
+      }
+      return r;
+    }
+
+  };
+
+}).call(this);