feat: split legacy/payment apps via APP_MODE flag

apps/mobile_app/lib/core/config/app_mode.dart

@@ -0,0 +1,20 @@
+/// Compile-time constant that controls which app the splash screen
+/// navigates to when the app starts.
+///
+/// Set via `--dart-define=APP_MODE=payment` (or `legacy`) at launch time.
+/// Defaults to `legacy` to preserve historical behavior when no flag is
+/// passed (e.g. `flutter run` from CLI without arguments).
+///
+/// Used only for local development to switch between the legacy app
+/// (watch/device control) and the payment app (Treezor wallet) without
+/// needing separate flavors or entry points.
+const String appMode = String.fromEnvironment(
+  'APP_MODE',
+  defaultValue: 'legacy',
+);
+
+/// Whether the app should boot into the payment (Treezor wallet) flow.
+bool get isPaymentMode => appMode == 'payment';
+
+/// Whether the app should boot into the legacy (watch/device) flow.
+bool get isLegacyMode => appMode == 'legacy';

apps/mobile_app/lib/core/init_app.dart

@@ -7,6 +7,7 @@ import 'package:design_system/design_system.dart';
 import 'package:sca_treezor/sca_treezor.dart';
 import 'package:sf_app_platform/config/env/environment_enum.dart';
 import 'package:sf_app_platform/config/env/questia_env_config.dart';
+import 'package:sf_app_platform/core/config/app_mode.dart';
 import 'package:sf_app_platform/navigation/app_router.dart';
 import 'package:sf_app_platform/save_family_app.dart';
 import 'package:navigation/navigation.dart';
@@ -30,9 +31,11 @@ Future<void> initApp(EnvironmentEnum env) async {
   await configureDependencies(
     QuestiaEnvConfig(),
     log: env.isDevelopment || kDebugMode,
-    onTokenExpired: () => appRouter.go(
-      AppRoutes.legacyLogin,
-    ), //change to payments app to AppRoutes.scaTreezor
+    // Treezor-specific detection (message + 500) runs in both modes;
+    // only the destination route differs based on the active app mode.
+    onTokenExpired: isPaymentMode
+        ? () => appRouter.go(AppRoutes.scaTreezor)
+        : () => appRouter.go(AppRoutes.legacyLogin),
     onUnauthorized: () async {
       final currentLocation =
           appRouter.routerDelegate.currentConfiguration.uri.path;
@@ -41,7 +44,7 @@ Future<void> initApp(EnvironmentEnum env) async {
         await GetIt.I<TreezorWalletConnectionService>().logout();
       } catch (_) {}
       await clearSessionData();
-      appRouter.go(AppRoutes.legacyLogin);
+      appRouter.go(isPaymentMode ? AppRoutes.login : AppRoutes.legacyLogin);
     },
   );
 

apps/mobile_app/lib/navigation/app_router.dart

@@ -17,13 +17,33 @@ import 'package:notifications/notifications.dart';
 import 'package:payments/payments.dart';
 import 'package:profile/profile.dart';
 import 'package:settings/settings.dart';
+import 'package:sf_app_platform/core/config/app_mode.dart';
 import 'package:splash/splash.dart';
 
 final GlobalKey<NavigatorState> rootNavigatorKey = GlobalKey<NavigatorState>();
 
 late final GoRouter appRouter;
 
+/// Maps the splash's session check result to the destination route based
+/// on the active [appMode]. Set `--dart-define=APP_MODE=payment` (or use
+/// the `(Payment)` launch configurations) to boot into the payment app.
+const _legacySplashRouteMap = <InitialRoute, String>{
+  InitialRoute.onboarding: AppRoutes.legacyOnboarding,
+  InitialRoute.login: AppRoutes.legacyLogin,
+  InitialRoute.home: AppRoutes.controlPanel,
+};
+
+const _paymentSplashRouteMap = <InitialRoute, String>{
+  InitialRoute.onboarding: AppRoutes.onboarding,
+  InitialRoute.login: AppRoutes.login,
+  InitialRoute.home: AppRoutes.dashboardHome,
+};
+
 void configureAppRouter() {
+  final splashRouteMap = isPaymentMode
+      ? _paymentSplashRouteMap
+      : _legacySplashRouteMap;
+
   appRouter = GoRouter(
     navigatorKey: rootNavigatorKey,
     initialLocation: AppRoutes.splash,
@@ -32,7 +52,7 @@ void configureAppRouter() {
       GoRoute(
         path: AppRoutes.splash,
         name: 'splash',
-        pageBuilder: SplashBuilder().buildPage,
+        pageBuilder: SplashBuilder(routeMap: splashRouteMap).buildPage,
       ),
       StatefulShellRoute.indexedStack(
         builder: (context, state, navShell) {

apps/mobile_app/lib/save_family_app.dart

@@ -2,6 +2,7 @@ import 'package:auth/auth.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_localizations/flutter_localizations.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:sf_app_platform/core/config/app_mode.dart';
 import 'package:sf_app_platform/navigation/app_router.dart';
 import 'package:navigation/navigation.dart';
 import 'package:sf_app_platform/providers/app_state_provider.dart';
@@ -24,48 +25,58 @@ class SaveFamilyApp extends ConsumerStatefulWidget {
 
 class SaveFamilyAppState extends ConsumerState<SaveFamilyApp>
     with WidgetsBindingObserver {
-  late final WalletHeartbeatService walletHeartbeat;
-  late final LegacyHeartbeatService legacyHeartbeat;
+  WalletHeartbeatService? _walletHeartbeat;
+  LegacyHeartbeatService? _legacyHeartbeat;
 
   @override
   void initState() {
     super.initState();
     WidgetsBinding.instance.addObserver(this);
-    walletHeartbeat = WalletHeartbeatService(
-      repository: ref.read(treezorRepositoryProvider),
-      sessionLocal: SessionLocalDatasourceImpl(),
-      onError: () => appRouter.go(
-        AppRoutes.legacyLogin,
-      ), //change to payments app to AppRoutes.scaTreezor
-    );
-    legacyHeartbeat = LegacyHeartbeatService(
-      repository: GetIt.I<QuestiaRepository>(),
-      onUnauthorized: () {
-        clearSessionData();
-        appRouter.go(AppRoutes.legacyLogin);
-      },
-    );
+
+    if (isPaymentMode) {
+      _walletHeartbeat = WalletHeartbeatService(
+        repository: ref.read(treezorRepositoryProvider),
+        sessionLocal: SessionLocalDatasourceImpl(),
+        onError: () => appRouter.go(AppRoutes.scaTreezor),
+      );
+    }
+
+    if (isLegacyMode) {
+      _legacyHeartbeat = LegacyHeartbeatService(
+        repository: GetIt.I<QuestiaRepository>(),
+        onUnauthorized: () {
+          clearSessionData();
+          appRouter.go(AppRoutes.legacyLogin);
+        },
+      );
+      appRouter.routerDelegate.addListener(_onRouteChanged);
+    }
+
     onBeforeSessionCleared = () {
-      walletHeartbeat.stop();
-      legacyHeartbeat.stop();
+      _walletHeartbeat?.stop();
+      _legacyHeartbeat?.stop();
     };
-    appRouter.routerDelegate.addListener(_onRouteChanged);
   }
 
   void _onRouteChanged() {
+    final heartbeat = _legacyHeartbeat;
+    if (heartbeat == null) return;
+
     final location = appRouter.routerDelegate.currentConfiguration.uri.path;
     if (location.startsWith(AppRoutes.legacyDashboard)) {
-      legacyHeartbeat.start();
+      heartbeat.start();
     } else {
-      legacyHeartbeat.stop();
+      heartbeat.stop();
     }
   }
 
   @override
   void dispose() {
-    appRouter.routerDelegate.removeListener(_onRouteChanged);
-    walletHeartbeat.stop();
-    legacyHeartbeat.stop();
+    if (isLegacyMode) {
+      appRouter.routerDelegate.removeListener(_onRouteChanged);
+    }
+    _walletHeartbeat?.stop();
+    _legacyHeartbeat?.stop();
     WidgetsBinding.instance.removeObserver(this);
     super.dispose();
   }
@@ -75,12 +86,14 @@ class SaveFamilyAppState extends ConsumerState<SaveFamilyApp>
     debugPrint('State: $state');
     ref.read(appLifecycleStateProvider.notifier).setState(state);
     if (state == AppLifecycleState.resumed) {
-      // walletHeartbeat.start();
-      _onRouteChanged();
+      _walletHeartbeat?.start();
+      if (isLegacyMode) {
+        _onRouteChanged();
+      }
       ref.read(permissionsProvider.notifier).checkPermissions();
     } else if (state == AppLifecycleState.paused) {
-      // walletHeartbeat.stop();
-      legacyHeartbeat.stop();
+      _walletHeartbeat?.stop();
+      _legacyHeartbeat?.stop();
     }
     super.didChangeAppLifecycleState(state);
   }