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/react-native/React/Views/RCTActivityIndicatorViewManager.m

@@ -0,0 +1,64 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#import "RCTActivityIndicatorViewManager.h"
+
+#import "RCTActivityIndicatorView.h"
+#import "RCTConvert.h"
+
+@implementation RCTConvert (UIActivityIndicatorView)
+
+// NOTE: It's pointless to support UIActivityIndicatorViewStyleGray
+// as we can set the color to any arbitrary value that we want to
+
+RCT_ENUM_CONVERTER(
+    UIActivityIndicatorViewStyle,
+    (@{
+      @"large" : @(UIActivityIndicatorViewStyleLarge),
+      @"small" : @(UIActivityIndicatorViewStyleMedium),
+    }),
+    UIActivityIndicatorViewStyleLarge,
+    integerValue)
+
+@end
+
+@implementation RCTActivityIndicatorViewManager
+
+RCT_EXPORT_MODULE()
+
+- (UIView *)view
+{
+  return [RCTActivityIndicatorView new];
+}
+
+RCT_EXPORT_VIEW_PROPERTY(color, UIColor)
+RCT_EXPORT_VIEW_PROPERTY(hidesWhenStopped, BOOL)
+RCT_CUSTOM_VIEW_PROPERTY(size, UIActivityIndicatorViewStyle, UIActivityIndicatorView)
+{
+  /*
+    Setting activityIndicatorViewStyle overrides the color, so restore the original color
+    after setting the indicator style.
+  */
+  UIColor *oldColor = view.color;
+  view.activityIndicatorViewStyle =
+      json ? [RCTConvert UIActivityIndicatorViewStyle:json] : defaultView.activityIndicatorViewStyle;
+  view.color = oldColor;
+}
+
+RCT_CUSTOM_VIEW_PROPERTY(animating, BOOL, UIActivityIndicatorView)
+{
+  BOOL animating = json ? [RCTConvert BOOL:json] : [defaultView isAnimating];
+  if (animating != [view isAnimating]) {
+    if (animating) {
+      [view startAnimating];
+    } else {
+      [view stopAnimating];
+    }
+  }
+}
+
+@end