feat(settings): soundEnabled provider gates SFX and haptics

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

lib/state/providers.dart

@@ -11,6 +11,7 @@ import '../services/consent_service.dart';
 import '../services/iap_service.dart';
 import 'ads_notifier.dart';
 import 'endless_best_notifier.dart';
+import 'sound_notifier.dart';
 import 'game_session_notifier.dart';
 import 'progress_notifier.dart';
 import 'season_flow_notifier.dart';
@@ -22,8 +23,12 @@ final gameSessionProvider =
   GameSessionNotifier.new,
 );
 
+final soundEnabledProvider =
+    NotifierProvider<SoundEnabledNotifier, bool>(SoundEnabledNotifier.new);
+
 final audioServiceProvider = Provider<AudioService>((ref) {
-  final service = AudioService();
+  final service = AudioService(enabled: ref.read(soundEnabledProvider));
+  ref.listen<bool>(soundEnabledProvider, (_, next) => service.enabled = next);
   ref.onDispose(service.dispose);
   return service;
 });

lib/state/sound_notifier.dart

@@ -0,0 +1,17 @@
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+
+import 'providers.dart';
+
+/// SFX + gameplay haptics on/off, seeded from the save repository.
+class SoundEnabledNotifier extends Notifier<bool> {
+  @override
+  bool build() => ref.read(saveRepositoryProvider).soundEnabled;
+
+  Future<void> toggle() => set(!state);
+
+  Future<void> set(bool value) async {
+    if (state == value) return;
+    await ref.read(saveRepositoryProvider).setSoundEnabled(value);
+    state = value;
+  }
+}

lib/ui/screens/game_screen.dart

@@ -120,16 +120,17 @@ class _GameScreenState extends ConsumerState<GameScreen>
     final audio = ref.read(audioServiceProvider);
     if (prev?.fxTick != next.fxTick && next.lastPlacement != null) {
       final placement = next.lastPlacement!;
+      final hapticsOn = ref.read(soundEnabledProvider);
       if (placement.linesCleared > 0) {
         audio.play(placement.comboStreak >= 2 ? Sfx.combo : Sfx.clear);
-        HapticFeedback.mediumImpact();
+        if (hapticsOn) HapticFeedback.mediumImpact();
         if (placement.comboStreak >= 4) {
-          HapticFeedback.heavyImpact();
+          if (hapticsOn) HapticFeedback.heavyImpact();
           _shake.forward(from: 0);
         }
       } else {
         audio.play(Sfx.place);
-        HapticFeedback.lightImpact();
+        if (hapticsOn) HapticFeedback.lightImpact();
       }
       ref.read(tutorialProvider.notifier).onPlaced();
       if (placement.linesCleared > 0) {

test/state/sound_notifier_test.dart

@@ -0,0 +1,21 @@
+import 'package:block_seasons/data/save_repository.dart';
+import 'package:block_seasons/state/providers.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+
+void main() {
+  test('reads persisted sound flag and toggles + persists', () async {
+    SharedPreferences.setMockInitialValues({});
+    final repo = await SaveRepository.open();
+    final c = ProviderContainer(
+      overrides: [saveRepositoryProvider.overrideWithValue(repo)],
+    );
+    addTearDown(c.dispose);
+
+    expect(c.read(soundEnabledProvider), isTrue);
+    await c.read(soundEnabledProvider.notifier).toggle();
+    expect(c.read(soundEnabledProvider), isFalse);
+    expect(repo.soundEnabled, isFalse);
+  });
+}