fix(ui): honor disabled hero animations

lib/app.dart

@@ -192,16 +192,18 @@ class SpotiFLACApp extends ConsumerWidget {
           // dialogs stay centered on large/foldable devices.
           builder: (context, child) {
             final mediaQuery = MediaQuery.of(context);
+            final appContent = _OrientationFade(
+              child: child ?? const SizedBox.shrink(),
+            );
             return MediaQuery(
               data: mediaQuery.copyWith(displayFeatures: const []),
-              // Global Hero kill switch: heroes below a disabled HeroMode
-              // never register, so no flights run on any navigator.
-              child: HeroMode(
-                enabled: heroAnimationsEnabled,
-                child: _OrientationFade(
-                  child: child ?? const SizedBox.shrink(),
-                ),
-              ),
+              // HeroMode only affects heroes below a *route* subtree. At this
+              // level it sits above the router's Navigator, so the controller
+              // never encounters it while collecting heroes. Removing the
+              // inherited controller disables flights on the root Navigator.
+              child: heroAnimationsEnabled
+                  ? appContent
+                  : HeroControllerScope.none(child: appContent),
             );
           },
           routerConfig: router,

lib/screens/main_shell.dart

@@ -506,6 +506,9 @@ class _MainShellState extends ConsumerState<MainShell>
     final showStore = ref.watch(
       settingsProvider.select((s) => s.showExtensionStore),
     );
+    final heroAnimationsEnabled = ref.watch(
+      settingsProvider.select((s) => s.heroAnimationsEnabled),
+    );
     ShellNavigationService.syncState(
       currentTabIndex: _currentIndex,
       showRepoTab: showStore,
@@ -519,12 +522,14 @@ class _MainShellState extends ConsumerState<MainShell>
         key: const ValueKey('tab-home'),
         navigatorKey: _homeTabNavigatorKey,
         observers: [_homePreviewStopObserver],
+        heroAnimationsEnabled: heroAnimationsEnabled,
         child: const HomeTab(),
       ),
       _TabNavigator(
         key: const ValueKey('tab-library'),
         navigatorKey: _libraryTabNavigatorKey,
         observers: [_libraryPreviewStopObserver],
+        heroAnimationsEnabled: heroAnimationsEnabled,
         child: _LibraryTabRoot(parentPageController: _pageController),
       ),
       if (showStore)
@@ -532,6 +537,7 @@ class _MainShellState extends ConsumerState<MainShell>
           key: const ValueKey('tab-repo'),
           navigatorKey: _repoTabNavigatorKey,
           observers: [_repoPreviewStopObserver],
+          heroAnimationsEnabled: heroAnimationsEnabled,
           child: const RepoTab(),
         ),
       const SettingsTab(),
@@ -750,12 +756,14 @@ class _TabNavigator extends StatefulWidget {
   final GlobalKey<NavigatorState> navigatorKey;
   final Widget child;
   final List<NavigatorObserver> observers;
+  final bool heroAnimationsEnabled;
 
   const _TabNavigator({
     super.key,
     required this.navigatorKey,
     required this.child,
     this.observers = const [],
+    required this.heroAnimationsEnabled,
   });
 
   @override
@@ -778,7 +786,10 @@ class _TabNavigatorState extends State<_TabNavigator> {
   Widget build(BuildContext context) {
     return Navigator(
       key: widget.navigatorKey,
-      observers: [_heroController, ...widget.observers],
+      observers: [
+        if (widget.heroAnimationsEnabled) _heroController,
+        ...widget.observers,
+      ],
       onGenerateInitialRoutes: (_, _) => [
         MaterialPageRoute<void>(builder: (_) => widget.child),
       ],

test/hero_animation_controller_test.dart

@@ -0,0 +1,62 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  testWidgets(
+    'HeroControllerScope.none reaches the MaterialApp root Navigator',
+    (tester) async {
+      final navigatorKey = GlobalKey<NavigatorState>();
+
+      await tester.pumpWidget(
+        MaterialApp(
+          navigatorKey: navigatorKey,
+          builder: (context, child) =>
+              HeroControllerScope.none(child: child ?? const SizedBox.shrink()),
+          home: const SizedBox.shrink(),
+        ),
+      );
+
+      final navigatorContext = navigatorKey.currentContext!;
+      final scope = navigatorContext
+          .getInheritedWidgetOfExactType<HeroControllerScope>();
+      expect(scope, isNotNull);
+      expect(scope!.controller, isNull);
+    },
+  );
+
+  testWidgets('removing an explicit HeroController detaches it', (
+    tester,
+  ) async {
+    final navigatorKey = GlobalKey<NavigatorState>();
+    final controller = MaterialApp.createMaterialHeroController();
+    var enabled = true;
+    late StateSetter setHostState;
+
+    await tester.pumpWidget(
+      MaterialApp(
+        home: HeroControllerScope.none(
+          child: StatefulBuilder(
+            builder: (context, setState) {
+              setHostState = setState;
+              return Navigator(
+                key: navigatorKey,
+                observers: [if (enabled) controller],
+                onGenerateRoute: (_) => MaterialPageRoute<void>(
+                  builder: (_) => const SizedBox.shrink(),
+                ),
+              );
+            },
+          ),
+        ),
+      ),
+    );
+
+    expect(controller.navigator, same(navigatorKey.currentState));
+
+    setHostState(() => enabled = false);
+    await tester.pump();
+
+    expect(controller.navigator, isNull);
+    controller.dispose();
+  });
+}