fix(alarm): fail-safe alarm system overhaul (SDD alarm-system-overhaul, slice A)

Root-cause fix for the unstoppable-alarm incident (alarm rang 15 minutes,
only uninstall silenced it) plus systematic hardening of every stop path.

Native (Kotlin):
- Verified stop: stopActiveAlarm now derives its result from the real
  post-teardown state (companion instance + synchronous stopEverything +
  activeRingingId check) instead of reporting unconditional success.
- Atomic teardown: every stop path (stop action, notification button,
  snooze, missed, onDestroy, startForeground failure) funnels through one
  stopEverything() covering audio, wakelock, notification, foreground
  state and firing-record cleanup; player.release() guarded.
- Bounded ringing: 10-minute auto-silence armed via AlarmManager fires a
  FIRED->MISSED transition with a localized missed-alarm notification;
  repeating alarms keep their native rearm, deleted alarms never produce
  ghost MISSED notifications.
- Durable firing record with onStartCommand re-validation (resurrection
  guard) and boot-time stale cleanup; firing records cleared on every
  refuse/mismatch/cancel path.
- New notification-only dismissal channel (dismissAlarmNotificationOnly)
  so UI-level dedup can never kill a live ring's audio.

Flutter (Dart):
- Stop/disable/edit/delete of a ringing alarm always attempt to silence
  it; on native-query failure the stop falls back toward silence via the
  id-scoped legacy stop.
- Verified-stop results surface failures: the ringing screen keeps
  dismiss-by-design on success, but on a verified failure it stays up
  with a persistent force-stop banner (guarded against double-dismiss)
  and auto-dismisses if the ring ends externally (missed/notification).
- Missed events sync alarm bookkeeping without opening the ringing UI.
- 4 new l10n keys translated across all 13 locales (ARB guard green).

550 tests green, analyzer clean. Reviewed in 3 adversarial 4-lens rounds
(2 deterministic + 1 refuter-corroborated critical fixed); formal
gentle-ai receipt waived by maintainer authorization (correction scope
legitimately exceeded the frozen genesis paths). On-device QA checklist
in openspec/changes/alarm-system-overhaul/tasks.md pending before
archive.

lib/app.dart

@@ -281,6 +281,12 @@ class _PaginaPrincipalState extends State<_PaginaPrincipal>
       // nothing to open for this event.
       return;
     }
+    if (evento.accion == EventoAlarmaAndroid.accionMissed) {
+      // EstadoAlarmas' own native-event listener already recorded this
+      // transition (RES-1); the ring already ended, so opening the ringing
+      // screen here would only show a stale, already-silent alarm.
+      return;
+    }
     final estado = context.read<EstadoAlarmas>();
     if (estado.alarmas.isEmpty) {
       await estado.cargarPersistidasSinRecalcular();
@@ -361,15 +367,14 @@ class _PaginaPrincipalState extends State<_PaginaPrincipal>
       );
       // A duplicate delivery of the SAME ring's own fire event (the live
       // eventosAlarma stream and the one-shot obtenerEventoInicial() read
-      // the same native event and can both reach here) must be a no-op:
-      // ocultarNotificacionAlarma -> dismissAlarmNotification unconditionally
-      // stops PluriWaveAlarmService for that id on the native side, which
-      // would tear down the currently-ringing service and undo the
-      // ring-scoped media-volume override long before the real handoff.
-      // Only hide the notification when a genuinely DIFFERENT alarm fired
-      // while this one is active (single-ring-at-a-time by design).
+      // the same native event and can both reach here) must be a no-op.
+      // When a genuinely DIFFERENT alarm fired while this one is active
+      // (single-ring-at-a-time by design), hide ONLY its notification
+      // (RES-1): ocultarNotificacionAlarma -> dismissAlarmNotification
+      // unconditionally stops PluriWaveAlarmService, which would silently
+      // kill the OTHER alarm's ring if it is the one genuinely sounding.
       if (alarma.id != _alarmaSonandoId) {
-        await alarmas.android.ocultarNotificacionAlarma(alarma.id);
+        await alarmas.android.ocultarSoloNotificacion(alarma.id);
       }
       return;
     }

lib/estado/estado_alarmas.dart

@@ -54,6 +54,10 @@ class EstadoAlarmas extends ChangeNotifier {
   bool _cargando = false;
   String? _error;
 
+  /// Last alarm id recorded as MISSED (RES-1): lets the ringing screen
+  /// detect an external end-of-ring for its own alarm and reconcile.
+  String? ultimaAlarmaPerdidaId;
+
   List<AlarmaMusical> get alarmas => List.unmodifiable(_alarmas);
   List<RangoVacaciones> get vacaciones => List.unmodifiable(_vacaciones);
   List<ExcepcionAlarma> get excepciones => List.unmodifiable(_excepciones);
@@ -100,6 +104,10 @@ class EstadoAlarmas extends ChangeNotifier {
     debugPrint(
       '[PluriWave][alarmas] guardar id=${alarma.id} activa=${alarma.activa} hora=${alarma.hora}:${alarma.minuto} tipo=${alarma.tipoProgramacion.name}',
     );
+    // Mutation-while-ringing stop guard (SS-1a/SS-1b): fires BEFORE the save
+    // persists so an edit/toggle-off of the currently-ringing alarm always
+    // silences it first.
+    await _detenerSiEstaSonando(alarma.id);
     final config = await servicio.guardarAlarma(alarma);
     _aplicar(config);
     try {
@@ -156,11 +164,40 @@ class EstadoAlarmas extends ChangeNotifier {
     debugPrint('[PluriWave][alarmas] eliminar id=$id');
     final config = await servicio.eliminarAlarma(id);
     _aplicar(config);
-    await android.detenerSonidoNativo(id);
+    // Deleting the ringing alarm stops audio (SS-1c, regression lock): the
+    // centralized guard runs before cancelar, same as guardarAlarma.
+    await _detenerSiEstaSonando(id);
     await android.cancelar(id);
     notifyListeners();
   }
 
+  /// Centralized mutation-while-ringing stop guard (Decision 5): every
+  /// mutation of the currently-ringing alarm routes through this ONE check
+  /// instead of per-call-site logic, so a mutation of a DIFFERENT (non-
+  /// ringing) alarm never touches the live ring (SS-1d).
+  Future<void> _detenerSiEstaSonando(String id) async {
+    try {
+      final sonando = await android.alarmaSonandoId();
+      if (sonando == id) {
+        await android.detenerSonidoActivo();
+      }
+    } catch (e) {
+      debugPrint('[PluriWave][alarmas] detenerSiEstaSonando ERROR $e');
+      // Fail-toward-silence (Finding 2, eliminarAlarma regression): a failed
+      // query must not silently skip the stop when the alarm might genuinely
+      // be ringing. Fall back to the id-scoped legacy stop (the native side
+      // no-ops safely on a mismatch) inside its own try/catch so this outer
+      // flow (guardarAlarma/eliminarAlarma) always proceeds regardless.
+      try {
+        await android.detenerSonidoNativo(id);
+      } catch (fallbackError) {
+        debugPrint(
+          '[PluriWave][alarmas] detenerSiEstaSonando fallback ERROR $fallbackError',
+        );
+      }
+    }
+  }
+
   Future<void> cambiarActiva(AlarmaMusical alarma, bool activa) async {
     await guardarAlarma(alarma.copyWith(activa: activa));
   }
@@ -271,6 +308,7 @@ class EstadoAlarmas extends ChangeNotifier {
 
   Future<void> finalizarEjecucion(String alarmaId) async {
     debugPrint('[PluriWave][alarmas] finalizar ejecucion id=$alarmaId');
+    _error = null;
     final alarma = _buscarAlarma(alarmaId);
     final ejecucion =
         alarma?.snoozeOrigen ??
@@ -278,12 +316,34 @@ class EstadoAlarmas extends ChangeNotifier {
         alarma?.snoozeHasta ??
         DateTime.now();
     await android.ocultarNotificacionAlarma(alarmaId);
+    // Stop/Snooze Result Verification (SS-2a/SS-2b): the Stop path calls the
+    // id-agnostic fail-safe stop directly (it always targets whatever is
+    // ringing). `detenido` reflects the VERIFIED native teardown state
+    // (activeRingingId cleared same-process after a synchronous stop), not a
+    // literal dispatch acknowledgement, so a genuine failure is never
+    // swallowed.
+    final resultado = await android.detenerSonidoActivo();
+    if (!resultado.detenido) {
+      _error = 'No se pudo confirmar que la alarma dejo de sonar.';
+    }
     final config = await servicio.completarEjecucion(alarmaId, ejecucion);
     _aplicar(config);
     await _sincronizarTodas();
     notifyListeners();
   }
 
+  /// Retryable force-stop affordance (SS-3b): re-invokes the same fail-safe
+  /// stop; success clears the recorded failure, another failure keeps it.
+  Future<void> forzarDetencion(String alarmaId) async {
+    debugPrint('[PluriWave][alarmas] forzar detencion id=$alarmaId');
+    final resultado = await android.detenerSonidoActivo();
+    _error =
+        resultado.detenido
+            ? null
+            : 'No se pudo detener la alarma. Intentalo de nuevo.';
+    notifyListeners();
+  }
+
   Future<void> crearRangoVacaciones(RangoVacaciones rango) async {
     final nuevos = [..._vacaciones, rango];
     await guardarVacaciones(nuevos);
@@ -319,6 +379,10 @@ class EstadoAlarmas extends ChangeNotifier {
       await _registrarCancelacionSnoozeNativa(evento);
       return;
     }
+    if (evento.accion == EventoAlarmaAndroid.accionMissed) {
+      await _registrarEjecucionPerdida(evento);
+      return;
+    }
     if (evento.accion != EventoAlarmaAndroid.accionSnoozed) return;
     if (evento.alarmaId.isEmpty || evento.snoozeUntilMillis <= 0) return;
     final hasta = DateTime.fromMillisecondsSinceEpoch(evento.snoozeUntilMillis);
@@ -366,6 +430,29 @@ class EstadoAlarmas extends ChangeNotifier {
     }
   }
 
+  /// Records a native auto-silence (MISSED) transition (Phase 6): the native
+  /// scheduler already rearmed the next occurrence (repeating) or left it
+  /// disabled (one-shot) at fire time, so this only marks the occurrence
+  /// handled -- it MUST NOT call android.programar again.
+  Future<void> _registrarEjecucionPerdida(EventoAlarmaAndroid evento) async {
+    if (evento.alarmaId.isEmpty) return;
+    final origen =
+        evento.occurrenceAtMillis > 0
+            ? DateTime.fromMillisecondsSinceEpoch(evento.occurrenceAtMillis)
+            : DateTime.now();
+    debugPrint(
+      '[PluriWave][alarmas] ejecucion perdida id=${evento.alarmaId} origen=${origen.toIso8601String()}',
+    );
+    try {
+      final config = await servicio.completarEjecucion(evento.alarmaId, origen);
+      _aplicar(config);
+      ultimaAlarmaPerdidaId = evento.alarmaId;
+      notifyListeners();
+    } catch (e) {
+      debugPrint('[PluriWave][alarmas] ejecucion perdida ERROR $e');
+    }
+  }
+
   Future<void> _sincronizarEjecucionesGestionadasPorAndroid() async {
     try {
       final ejecuciones = await android.obtenerEjecucionesNativasGestionadas();

lib/l10n/app_ar.arb

@@ -466,6 +466,15 @@
   "ringingInternalAudioActive": "يرن باستخدام الصوت الداخلي الآمن.",
   "ringingPreparingInternalAudio": "جارٍ تجهيز الصوت الداخلي الآمن.",
   "stopAlarmAction": "إيقاف المنبه",
+  "alarmStopFailedMessage": "تعذّر التأكد من إيقاف المنبه. حاول مرة أخرى.",
+  "alarmForceStopAction": "إيقاف قسري",
+  "alarmMissedNotificationTitle": "منبه فائت",
+  "alarmMissedNotificationText": "تم كتم {name} تلقائيًا بعد 10 دقائق.",
+  "@alarmMissedNotificationText": {
+    "placeholders": {
+      "name": {}
+    }
+  },
   "pauseAction": "إيقاف مؤقت",
   "miniPlayerOpenLabel": "فتح المشغل لـ {stationName}",
   "@miniPlayerOpenLabel": {

lib/l10n/app_bn.arb

@@ -466,6 +466,15 @@
   "ringingInternalAudioActive": "নিরাপদ অভ্যন্তরীণ শব্দ দিয়ে বাজছে।",
   "ringingPreparingInternalAudio": "নিরাপদ অভ্যন্তরীণ শব্দ প্রস্তুত হচ্ছে।",
   "stopAlarmAction": "অ্যালার্ম বন্ধ করুন",
+  "alarmStopFailedMessage": "অ্যালার্ম বন্ধ হয়েছে তা নিশ্চিত করা যায়নি। আবার চেষ্টা করুন।",
+  "alarmForceStopAction": "জোর করে বন্ধ করুন",
+  "alarmMissedNotificationTitle": "মিস হওয়া অ্যালার্ম",
+  "alarmMissedNotificationText": "১০ মিনিট পর {name} স্বয়ংক্রিয়ভাবে নিঃশব্দ করা হয়েছে।",
+  "@alarmMissedNotificationText": {
+    "placeholders": {
+      "name": {}
+    }
+  },
   "pauseAction": "বিরতি দিন",
   "miniPlayerOpenLabel": "{stationName}-এর প্লেয়ার খুলুন",
   "@miniPlayerOpenLabel": {

lib/l10n/app_de.arb

@@ -466,6 +466,15 @@
   "ringingInternalAudioActive": "Wiedergabe mit internem Sicherheitston.",
   "ringingPreparingInternalAudio": "Interner Sicherheitston wird vorbereitet.",
   "stopAlarmAction": "Alarm stoppen",
+  "alarmStopFailedMessage": "Wir konnten nicht bestätigen, dass der Alarm gestoppt wurde. Versuche es erneut.",
+  "alarmForceStopAction": "Erzwungen stoppen",
+  "alarmMissedNotificationTitle": "Verpasster Alarm",
+  "alarmMissedNotificationText": "{name} wurde nach 10 Minuten automatisch stummgeschaltet.",
+  "@alarmMissedNotificationText": {
+    "placeholders": {
+      "name": {}
+    }
+  },
   "pauseAction": "Pausieren",
   "miniPlayerOpenLabel": "Wiedergabe für {stationName} öffnen",
   "@miniPlayerOpenLabel": {

lib/l10n/app_en.arb

@@ -466,6 +466,15 @@
   "ringingInternalAudioActive": "Playing with internal safe audio.",
   "ringingPreparingInternalAudio": "Preparing internal safe audio.",
   "stopAlarmAction": "Stop alarm",
+  "alarmStopFailedMessage": "We couldn't confirm the alarm stopped. Try again.",
+  "alarmForceStopAction": "Force stop",
+  "alarmMissedNotificationTitle": "Missed alarm",
+  "alarmMissedNotificationText": "{name} was silenced automatically after 10 minutes.",
+  "@alarmMissedNotificationText": {
+    "placeholders": {
+      "name": {}
+    }
+  },
   "pauseAction": "Pause",
   "miniPlayerOpenLabel": "Open player for {stationName}",
   "@miniPlayerOpenLabel": {

lib/l10n/app_es.arb

@@ -466,6 +466,11 @@
   "ringingInternalAudioActive": "Sonando con audio seguro interno.",
   "ringingPreparingInternalAudio": "Preparando audio seguro interno.",
   "stopAlarmAction": "Detener alarma",
+  "alarmStopFailedMessage": "No pudimos confirmar que la alarma se detuvo. Inténtalo de nuevo.",
+  "alarmForceStopAction": "Forzar detención",
+  "alarmMissedNotificationTitle": "Alarma perdida",
+  "alarmMissedNotificationText": "{name} se silenció automáticamente después de 10 minutos.",
+  "@alarmMissedNotificationText": {"placeholders": {"name": {}}},
   "pauseAction": "Pausar",
   "miniPlayerOpenLabel": "Abrir reproductor de {stationName}",
   "@miniPlayerOpenLabel": {"placeholders": {"stationName": {}}},

lib/l10n/app_fr.arb

@@ -466,6 +466,15 @@
   "ringingInternalAudioActive": "Son sécurisé interne en cours.",
   "ringingPreparingInternalAudio": "Préparation du son sécurisé interne.",
   "stopAlarmAction": "Arrêter l’alarme",
+  "alarmStopFailedMessage": "Nous n’avons pas pu confirmer l’arrêt de l’alarme. Réessayez.",
+  "alarmForceStopAction": "Forcer l’arrêt",
+  "alarmMissedNotificationTitle": "Alarme manquée",
+  "alarmMissedNotificationText": "{name} a été mise en sourdine automatiquement après 10 minutes.",
+  "@alarmMissedNotificationText": {
+    "placeholders": {
+      "name": {}
+    }
+  },
   "pauseAction": "Pause",
   "miniPlayerOpenLabel": "Ouvrir le lecteur de {stationName}",
   "@miniPlayerOpenLabel": {

lib/l10n/app_hi.arb

@@ -466,6 +466,15 @@
   "ringingInternalAudioActive": "सुरक्षित आंतरिक ध्वनि के साथ बज रहा है।",
   "ringingPreparingInternalAudio": "सुरक्षित आंतरिक ध्वनि तैयार हो रही है।",
   "stopAlarmAction": "अलार्म रोकें",
+  "alarmStopFailedMessage": "हम पुष्टि नहीं कर सके कि अलार्म बंद हुआ। फिर से कोशिश करें।",
+  "alarmForceStopAction": "जबरन बंद करें",
+  "alarmMissedNotificationTitle": "छूटा हुआ अलार्म",
+  "alarmMissedNotificationText": "10 मिनट बाद {name} अपने आप म्यूट कर दिया गया।",
+  "@alarmMissedNotificationText": {
+    "placeholders": {
+      "name": {}
+    }
+  },
   "pauseAction": "विराम दें",
   "miniPlayerOpenLabel": "{stationName} का प्लेयर खोलें",
   "@miniPlayerOpenLabel": {

lib/l10n/app_id.arb

@@ -466,6 +466,15 @@
   "ringingInternalAudioActive": "Berbunyi dengan audio internal aman.",
   "ringingPreparingInternalAudio": "Menyiapkan audio internal aman.",
   "stopAlarmAction": "Hentikan alarm",
+  "alarmStopFailedMessage": "Kami tidak dapat memastikan alarm berhenti. Coba lagi.",
+  "alarmForceStopAction": "Paksa berhenti",
+  "alarmMissedNotificationTitle": "Alarm terlewat",
+  "alarmMissedNotificationText": "{name} dibisukan secara otomatis setelah 10 menit.",
+  "@alarmMissedNotificationText": {
+    "placeholders": {
+      "name": {}
+    }
+  },
   "pauseAction": "Jeda",
   "miniPlayerOpenLabel": "Buka pemutar untuk {stationName}",
   "@miniPlayerOpenLabel": {

lib/l10n/app_it.arb

@@ -466,6 +466,15 @@
   "ringingInternalAudioActive": "Suono sicuro interno in riproduzione.",
   "ringingPreparingInternalAudio": "Preparazione del suono sicuro interno.",
   "stopAlarmAction": "Ferma sveglia",
+  "alarmStopFailedMessage": "Non siamo riusciti a confermare l’arresto della sveglia. Riprova.",
+  "alarmForceStopAction": "Forza arresto",
+  "alarmMissedNotificationTitle": "Sveglia mancata",
+  "alarmMissedNotificationText": "{name} è stata disattivata automaticamente dopo 10 minuti.",
+  "@alarmMissedNotificationText": {
+    "placeholders": {
+      "name": {}
+    }
+  },
   "pauseAction": "Pausa",
   "miniPlayerOpenLabel": "Apri il lettore per {stationName}",
   "@miniPlayerOpenLabel": {

lib/l10n/app_ja.arb

@@ -466,6 +466,15 @@
   "ringingInternalAudioActive": "安全な内部音で鳴っています。",
   "ringingPreparingInternalAudio": "安全な内部音を準備中です。",
   "stopAlarmAction": "アラームを停止",
+  "alarmStopFailedMessage": "アラームが停止したことを確認できませんでした。もう一度お試しください。",
+  "alarmForceStopAction": "強制停止",
+  "alarmMissedNotificationTitle": "アラームの聞き逃し",
+  "alarmMissedNotificationText": "{name}は10分後に自動的に消音されました。",
+  "@alarmMissedNotificationText": {
+    "placeholders": {
+      "name": {}
+    }
+  },
   "pauseAction": "一時停止",
   "miniPlayerOpenLabel": "{stationName}のプレーヤーを開く",
   "@miniPlayerOpenLabel": {

lib/l10n/app_pt.arb

@@ -466,6 +466,15 @@
   "ringingInternalAudioActive": "Tocando com som seguro interno.",
   "ringingPreparingInternalAudio": "Preparando som seguro interno.",
   "stopAlarmAction": "Parar alarme",
+  "alarmStopFailedMessage": "Não conseguimos confirmar que o alarme parou. Tente novamente.",
+  "alarmForceStopAction": "Forçar parada",
+  "alarmMissedNotificationTitle": "Alarme perdido",
+  "alarmMissedNotificationText": "{name} foi silenciado automaticamente após 10 minutos.",
+  "@alarmMissedNotificationText": {
+    "placeholders": {
+      "name": {}
+    }
+  },
   "pauseAction": "Pausar",
   "miniPlayerOpenLabel": "Abrir reprodutor de {stationName}",
   "@miniPlayerOpenLabel": {

lib/l10n/app_ru.arb

@@ -466,6 +466,15 @@
   "ringingInternalAudioActive": "Звонит с безопасным внутренним звуком.",
   "ringingPreparingInternalAudio": "Подготовка безопасного внутреннего звука.",
   "stopAlarmAction": "Остановить будильник",
+  "alarmStopFailedMessage": "Не удалось подтвердить, что будильник остановлен. Попробуйте снова.",
+  "alarmForceStopAction": "Принудительно остановить",
+  "alarmMissedNotificationTitle": "Пропущенный будильник",
+  "alarmMissedNotificationText": "{name} был автоматически отключён через 10 минут.",
+  "@alarmMissedNotificationText": {
+    "placeholders": {
+      "name": {}
+    }
+  },
   "pauseAction": "Пауза",
   "miniPlayerOpenLabel": "Открыть плеер для {stationName}",
   "@miniPlayerOpenLabel": {

lib/l10n/app_zh.arb

@@ -466,6 +466,15 @@
   "ringingInternalAudioActive": "正在使用内部安全音频响铃。",
   "ringingPreparingInternalAudio": "正在准备内部安全音频。",
   "stopAlarmAction": "停止闹钟",
+  "alarmStopFailedMessage": "无法确认闹钟已停止，请重试。",
+  "alarmForceStopAction": "强制停止",
+  "alarmMissedNotificationTitle": "错过的闹钟",
+  "alarmMissedNotificationText": "{name}已在10分钟后自动静音。",
+  "@alarmMissedNotificationText": {
+    "placeholders": {
+      "name": {}
+    }
+  },
   "pauseAction": "暂停",
   "miniPlayerOpenLabel": "打开 {stationName} 的播放器",
   "@miniPlayerOpenLabel": {

lib/l10n/gen/app_localizations.dart

@@ -1694,6 +1694,30 @@ abstract class AppLocalizations {
   /// **'Detener alarma'**
   String get stopAlarmAction;
 
+  /// No description provided for @alarmStopFailedMessage.
+  ///
+  /// In es, this message translates to:
+  /// **'No pudimos confirmar que la alarma se detuvo. Inténtalo de nuevo.'**
+  String get alarmStopFailedMessage;
+
+  /// No description provided for @alarmForceStopAction.
+  ///
+  /// In es, this message translates to:
+  /// **'Forzar detención'**
+  String get alarmForceStopAction;
+
+  /// No description provided for @alarmMissedNotificationTitle.
+  ///
+  /// In es, this message translates to:
+  /// **'Alarma perdida'**
+  String get alarmMissedNotificationTitle;
+
+  /// No description provided for @alarmMissedNotificationText.
+  ///
+  /// In es, this message translates to:
+  /// **'{name} se silenció automáticamente después de 10 minutos.'**
+  String alarmMissedNotificationText(Object name);
+
   /// No description provided for @pauseAction.
   ///
   /// In es, this message translates to:

lib/l10n/gen/app_localizations_ar.dart

@@ -899,6 +899,21 @@ class AppLocalizationsAr extends AppLocalizations {
   @override
   String get stopAlarmAction => 'إيقاف المنبه';
 
+  @override
+  String get alarmStopFailedMessage =>
+      'تعذّر التأكد من إيقاف المنبه. حاول مرة أخرى.';
+
+  @override
+  String get alarmForceStopAction => 'إيقاف قسري';
+
+  @override
+  String get alarmMissedNotificationTitle => 'منبه فائت';
+
+  @override
+  String alarmMissedNotificationText(Object name) {
+    return 'تم كتم $name تلقائيًا بعد 10 دقائق.';
+  }
+
   @override
   String get pauseAction => 'إيقاف مؤقت';
 

lib/l10n/gen/app_localizations_bn.dart

@@ -908,6 +908,21 @@ class AppLocalizationsBn extends AppLocalizations {
   @override
   String get stopAlarmAction => 'অ্যালার্ম বন্ধ করুন';
 
+  @override
+  String get alarmStopFailedMessage =>
+      'অ্যালার্ম বন্ধ হয়েছে তা নিশ্চিত করা যায়নি। আবার চেষ্টা করুন।';
+
+  @override
+  String get alarmForceStopAction => 'জোর করে বন্ধ করুন';
+
+  @override
+  String get alarmMissedNotificationTitle => 'মিস হওয়া অ্যালার্ম';
+
+  @override
+  String alarmMissedNotificationText(Object name) {
+    return '১০ মিনিট পর $name স্বয়ংক্রিয়ভাবে নিঃশব্দ করা হয়েছে।';
+  }
+
   @override
   String get pauseAction => 'বিরতি দিন';
 

lib/l10n/gen/app_localizations_de.dart

@@ -910,6 +910,21 @@ class AppLocalizationsDe extends AppLocalizations {
   @override
   String get stopAlarmAction => 'Alarm stoppen';
 
+  @override
+  String get alarmStopFailedMessage =>
+      'Wir konnten nicht bestätigen, dass der Alarm gestoppt wurde. Versuche es erneut.';
+
+  @override
+  String get alarmForceStopAction => 'Erzwungen stoppen';
+
+  @override
+  String get alarmMissedNotificationTitle => 'Verpasster Alarm';
+
+  @override
+  String alarmMissedNotificationText(Object name) {
+    return '$name wurde nach 10 Minuten automatisch stummgeschaltet.';
+  }
+
   @override
   String get pauseAction => 'Pausieren';
 

lib/l10n/gen/app_localizations_en.dart

@@ -903,6 +903,21 @@ class AppLocalizationsEn extends AppLocalizations {
   @override
   String get stopAlarmAction => 'Stop alarm';
 
+  @override
+  String get alarmStopFailedMessage =>
+      'We couldn\'t confirm the alarm stopped. Try again.';
+
+  @override
+  String get alarmForceStopAction => 'Force stop';
+
+  @override
+  String get alarmMissedNotificationTitle => 'Missed alarm';
+
+  @override
+  String alarmMissedNotificationText(Object name) {
+    return '$name was silenced automatically after 10 minutes.';
+  }
+
   @override
   String get pauseAction => 'Pause';
 

lib/l10n/gen/app_localizations_es.dart

@@ -907,6 +907,21 @@ class AppLocalizationsEs extends AppLocalizations {
   @override
   String get stopAlarmAction => 'Detener alarma';
 
+  @override
+  String get alarmStopFailedMessage =>
+      'No pudimos confirmar que la alarma se detuvo. Inténtalo de nuevo.';
+
+  @override
+  String get alarmForceStopAction => 'Forzar detención';
+
+  @override
+  String get alarmMissedNotificationTitle => 'Alarma perdida';
+
+  @override
+  String alarmMissedNotificationText(Object name) {
+    return '$name se silenció automáticamente después de 10 minutos.';
+  }
+
   @override
   String get pauseAction => 'Pausar';
 

lib/l10n/gen/app_localizations_fr.dart

@@ -913,6 +913,21 @@ class AppLocalizationsFr extends AppLocalizations {
   @override
   String get stopAlarmAction => 'Arrêter l’alarme';
 
+  @override
+  String get alarmStopFailedMessage =>
+      'Nous n’avons pas pu confirmer l’arrêt de l’alarme. Réessayez.';
+
+  @override
+  String get alarmForceStopAction => 'Forcer l’arrêt';
+
+  @override
+  String get alarmMissedNotificationTitle => 'Alarme manquée';
+
+  @override
+  String alarmMissedNotificationText(Object name) {
+    return '$name a été mise en sourdine automatiquement après 10 minutes.';
+  }
+
   @override
   String get pauseAction => 'Pause';
 

lib/l10n/gen/app_localizations_hi.dart

@@ -904,6 +904,21 @@ class AppLocalizationsHi extends AppLocalizations {
   @override
   String get stopAlarmAction => 'अलार्म रोकें';
 
+  @override
+  String get alarmStopFailedMessage =>
+      'हम पुष्टि नहीं कर सके कि अलार्म बंद हुआ। फिर से कोशिश करें।';
+
+  @override
+  String get alarmForceStopAction => 'जबरन बंद करें';
+
+  @override
+  String get alarmMissedNotificationTitle => 'छूटा हुआ अलार्म';
+
+  @override
+  String alarmMissedNotificationText(Object name) {
+    return '10 मिनट बाद $name अपने आप म्यूट कर दिया गया।';
+  }
+
   @override
   String get pauseAction => 'विराम दें';
 

lib/l10n/gen/app_localizations_id.dart

@@ -908,6 +908,21 @@ class AppLocalizationsId extends AppLocalizations {
   @override
   String get stopAlarmAction => 'Hentikan alarm';
 
+  @override
+  String get alarmStopFailedMessage =>
+      'Kami tidak dapat memastikan alarm berhenti. Coba lagi.';
+
+  @override
+  String get alarmForceStopAction => 'Paksa berhenti';
+
+  @override
+  String get alarmMissedNotificationTitle => 'Alarm terlewat';
+
+  @override
+  String alarmMissedNotificationText(Object name) {
+    return '$name dibisukan secara otomatis setelah 10 menit.';
+  }
+
   @override
   String get pauseAction => 'Jeda';
 

lib/l10n/gen/app_localizations_it.dart

@@ -910,6 +910,21 @@ class AppLocalizationsIt extends AppLocalizations {
   @override
   String get stopAlarmAction => 'Ferma sveglia';
 
+  @override
+  String get alarmStopFailedMessage =>
+      'Non siamo riusciti a confermare l’arresto della sveglia. Riprova.';
+
+  @override
+  String get alarmForceStopAction => 'Forza arresto';
+
+  @override
+  String get alarmMissedNotificationTitle => 'Sveglia mancata';
+
+  @override
+  String alarmMissedNotificationText(Object name) {
+    return '$name è stata disattivata automaticamente dopo 10 minuti.';
+  }
+
   @override
   String get pauseAction => 'Pausa';
 

lib/l10n/gen/app_localizations_ja.dart

@@ -875,6 +875,20 @@ class AppLocalizationsJa extends AppLocalizations {
   @override
   String get stopAlarmAction => 'アラームを停止';
 
+  @override
+  String get alarmStopFailedMessage => 'アラームが停止したことを確認できませんでした。もう一度お試しください。';
+
+  @override
+  String get alarmForceStopAction => '強制停止';
+
+  @override
+  String get alarmMissedNotificationTitle => 'アラームの聞き逃し';
+
+  @override
+  String alarmMissedNotificationText(Object name) {
+    return '$nameは10分後に自動的に消音されました。';
+  }
+
   @override
   String get pauseAction => '一時停止';
 

lib/l10n/gen/app_localizations_pt.dart

@@ -905,6 +905,21 @@ class AppLocalizationsPt extends AppLocalizations {
   @override
   String get stopAlarmAction => 'Parar alarme';
 
+  @override
+  String get alarmStopFailedMessage =>
+      'Não conseguimos confirmar que o alarme parou. Tente novamente.';
+
+  @override
+  String get alarmForceStopAction => 'Forçar parada';
+
+  @override
+  String get alarmMissedNotificationTitle => 'Alarme perdido';
+
+  @override
+  String alarmMissedNotificationText(Object name) {
+    return '$name foi silenciado automaticamente após 10 minutos.';
+  }
+
   @override
   String get pauseAction => 'Pausar';
 

lib/l10n/gen/app_localizations_ru.dart

@@ -909,6 +909,21 @@ class AppLocalizationsRu extends AppLocalizations {
   @override
   String get stopAlarmAction => 'Остановить будильник';
 
+  @override
+  String get alarmStopFailedMessage =>
+      'Не удалось подтвердить, что будильник остановлен. Попробуйте снова.';
+
+  @override
+  String get alarmForceStopAction => 'Принудительно остановить';
+
+  @override
+  String get alarmMissedNotificationTitle => 'Пропущенный будильник';
+
+  @override
+  String alarmMissedNotificationText(Object name) {
+    return '$name был автоматически отключён через 10 минут.';
+  }
+
   @override
   String get pauseAction => 'Пауза';
 

lib/l10n/gen/app_localizations_zh.dart

@@ -871,6 +871,20 @@ class AppLocalizationsZh extends AppLocalizations {
   @override
   String get stopAlarmAction => '停止闹钟';
 
+  @override
+  String get alarmStopFailedMessage => '无法确认闹钟已停止，请重试。';
+
+  @override
+  String get alarmForceStopAction => '强制停止';
+
+  @override
+  String get alarmMissedNotificationTitle => '错过的闹钟';
+
+  @override
+  String alarmMissedNotificationText(Object name) {
+    return '$name已在10分钟后自动静音。';
+  }
+
   @override
   String get pauseAction => '暂停';
 

lib/pantallas/pantalla_alarma_sonando.dart

@@ -30,9 +30,31 @@ class _PantallaAlarmaSonandoState extends State<PantallaAlarmaSonando> {
   /// (a second _dismissScreen would pop the route UNDER the alarm screen).
   bool _salidaEnCurso = false;
 
+  /// Retryable force-stop affordance (Finding A, spec `alarm-stop-safety` /
+  /// "Retryable Force-Stop Affordance"): true while a VERIFIED stop failure
+  /// (or an unknown-state exception) is outstanding. Unlike a timed SnackBar,
+  /// this drives a persistent in-screen banner that stays until a confirmed
+  /// stop clears it — the ring is still audible while this is true, so the
+  /// screen intentionally does NOT dismiss.
+  bool _falloDetencionVisible = false;
+
+  late final EstadoAlarmas _alarmas;
+
   @override
   void initState() {
     super.initState();
+    _alarmas = context.read<EstadoAlarmas>();
+    _alarmas.addListener(_alReconciliarFinExterno);
+  }
+
+  /// External end-of-ring reconciliation (RES-1): if this alarm's occurrence
+  /// gets recorded as MISSED while this screen is up, auto-dismiss instead of
+  /// leaving a stale ringing screen with no audio behind it.
+  void _alReconciliarFinExterno() {
+    if (_salidaEnCurso || !mounted) return;
+    if (_alarmas.ultimaAlarmaPerdidaId != widget.alarma.id) return;
+    _salidaEnCurso = true;
+    _dismissScreen();
   }
 
   /// Pure UI: the ring's audio is owned entirely by the native
@@ -43,15 +65,46 @@ class _PantallaAlarmaSonandoState extends State<PantallaAlarmaSonando> {
     if (_salidaEnCurso) return;
     _salidaEnCurso = true;
     final alarmas = context.read<EstadoAlarmas>();
-    // Dismiss is run from finally so a failing reschedule/teardown can never
-    // leave the ringing screen stuck open (which would also block the next
-    // ring via the _alarmaSonandoActiva guard in app.dart).
+    final alarmaId = widget.alarma.id;
     try {
-      await alarmas.finalizarEjecucion(widget.alarma.id);
+      await alarmas.finalizarEjecucion(alarmaId);
+      if (alarmas.error != null) {
+        // Verified stop failure (Finding A): the alarm is still ringing, so
+        // dismissing now would hide the only retry affordance. Reset the
+        // single-exit guard so a retry (this button again, back gesture, or
+        // the banner's own action below) can run the teardown again.
+        _salidaEnCurso = false;
+        if (mounted) setState(() => _falloDetencionVisible = true);
+        return;
+      }
     } catch (e) {
       debugPrint('[PluriWave][alarmas] finalizar ejecucion fallo: $e');
-    } finally {
+      // Unknown state (Finding A): treat exactly like a verified failure —
+      // stay and show the retry banner. The notification's native Stop
+      // action remains the out-of-band fallback, and PopScope already routes
+      // back through this same method on a subsequent back-press.
+      _salidaEnCurso = false;
+      if (mounted) setState(() => _falloDetencionVisible = true);
+      return;
+    }
+    if (mounted) _dismissScreen();
+  }
+
+  /// Retry action bound to the persistent force-stop banner (Finding A,
+  /// SS-3b): re-invokes the fail-safe stop directly; dismisses ONLY on a
+  /// confirmed success, otherwise the banner stays exactly as it was.
+  Future<void> _forzarDetencion() async {
+    if (_salidaEnCurso) return;
+    _salidaEnCurso = true;
+    final alarmas = context.read<EstadoAlarmas>();
+    await alarmas.forzarDetencion(widget.alarma.id);
+    if (alarmas.error == null) {
       if (mounted) _dismissScreen();
+    } else {
+      // Verified failure (RES-2): reset the guard so the banner's own retry
+      // action (or another button) can run the teardown again.
+      _salidaEnCurso = false;
+      if (mounted) setState(() {});
     }
   }
 
@@ -109,6 +162,7 @@ class _PantallaAlarmaSonandoState extends State<PantallaAlarmaSonando> {
 
   @override
   void dispose() {
+    _alarmas.removeListener(_alReconciliarFinExterno);
     super.dispose();
   }
 
@@ -209,6 +263,10 @@ class _PantallaAlarmaSonandoState extends State<PantallaAlarmaSonando> {
                     icon: const Icon(Icons.stop_rounded),
                     label: Text(l10n.stopAlarmAction),
                   ),
+                  if (_falloDetencionVisible) ...[
+                    const SizedBox(height: 14),
+                    _bannerFalloDetencion(context, l10n, tokens),
+                  ],
                 ],
               ),
             ).pluriFadeIn(context),
@@ -217,6 +275,37 @@ class _PantallaAlarmaSonandoState extends State<PantallaAlarmaSonando> {
       ),
     );
   }
+
+  /// Persistent force-stop retry banner (Finding A, spec `alarm-stop-safety`
+  /// / "Retryable Force-Stop Affordance"): an in-screen section rather than a
+  /// timed SnackBar, so it stays visible until [_forzarDetencion] confirms a
+  /// stop (or the screen is torn down externally) instead of auto-dismissing
+  /// after a fixed duration.
+  Widget _bannerFalloDetencion(
+    BuildContext context,
+    AppLocalizations l10n,
+    PluriWaveTokens tokens,
+  ) {
+    return Container(
+      padding: const EdgeInsets.all(12),
+      decoration: BoxDecoration(
+        color: tokens.warmCoral.withValues(alpha: 0.15),
+        borderRadius: BorderRadius.circular(16),
+        border: Border.all(color: tokens.warmCoral.withValues(alpha: 0.4)),
+      ),
+      child: Column(
+        mainAxisSize: MainAxisSize.min,
+        children: [
+          Text(l10n.alarmStopFailedMessage, textAlign: TextAlign.center),
+          const SizedBox(height: 8),
+          FilledButton.tonal(
+            onPressed: _forzarDetencion,
+            child: Text(l10n.alarmForceStopAction),
+          ),
+        ],
+      ),
+    );
+  }
 }
 
 String _hora(AlarmaMusical alarma) =>

lib/servicios/servicio_alarmas_android.dart

@@ -27,6 +27,10 @@ class EventoAlarmaAndroid {
   /// countdown notification ("Detener" while the app may be killed).
   static const accionSnoozeCancelled = 'snoozeCancelled';
 
+  /// Action reported when a fired alarm auto-silenced unattended after the
+  /// 10-minute bound (Decision 3), never a user-initiated stop.
+  static const accionMissed = 'missed';
+
   final String alarmaId;
   final String titulo;
   final String accion;
@@ -108,6 +112,36 @@ class DiagnosticoAlarmasAndroid {
   }
 }
 
+/// Fail-safe stop result (Decision 1). `detenido` reports whether a
+/// non-no-op teardown was dispatched (never silently swallowed); `alarmaId`
+/// is the id that was actually ringing, for Dart-side reconciliation.
+class ResultadoDetencion {
+  const ResultadoDetencion({
+    required this.detenido,
+    required this.estabaSonando,
+    this.alarmaId,
+  });
+
+  final bool detenido;
+  final bool estabaSonando;
+  final String? alarmaId;
+
+  /// A thrown channel error or a missing native response is treated as a
+  /// failure, never as an implicit success.
+  static const fallo = ResultadoDetencion(
+    detenido: false,
+    estabaSonando: false,
+  );
+
+  factory ResultadoDetencion.fromMap(Map<Object?, Object?> map) {
+    return ResultadoDetencion(
+      detenido: map['stopped'] as bool? ?? false,
+      estabaSonando: map['wasRinging'] as bool? ?? false,
+      alarmaId: map['activeAlarmId'] as String?,
+    );
+  }
+}
+
 class EjecucionAlarmaNativa {
   const EjecucionAlarmaNativa({
     required this.alarmaId,
@@ -137,7 +171,20 @@ abstract class PuertoAlarmasAndroid {
   Future<void> programar(AlarmaMusical alarma);
   Future<void> cancelar(String alarmaId);
   Future<void> ocultarNotificacionAlarma(String alarmaId);
+
+  /// Notification-only dismissal (RES-1): hides the fire notification for
+  /// [alarmaId] WITHOUT stopping native ring audio for any alarm. Used when a
+  /// genuinely different alarm rings while another one is still active.
+  Future<void> ocultarSoloNotificacion(String alarmaId);
   Future<void> detenerSonidoNativo(String alarmaId);
+
+  /// Synchronous companion snapshot (Decision 1): the id of the alarm
+  /// currently ringing natively, or null if none is.
+  Future<String?> alarmaSonandoId();
+
+  /// Id-agnostic fail-safe stop: silences whatever is ringing regardless of
+  /// which alarm the caller thinks is active, and reports a verified result.
+  Future<ResultadoDetencion> detenerSonidoActivo();
   Future<bool> solicitarPermisoAlarmasExactas();
   Future<bool> solicitarPermisoNotificaciones();
   Future<bool> solicitarPermisoPantallaCompleta();
@@ -195,6 +242,8 @@ class ServicioAlarmasAndroid implements PuertoAlarmasAndroid {
         'snoozeCountdownTemplate': _plantillaMinutos(l10n.snoozeCountdown),
         'openFolderTitle': l10n.openFolderChooserTitle,
         'openRecordingTitle': l10n.openRecordingChooserTitle,
+        'missedTitle': l10n.alarmMissedNotificationTitle,
+        'missedTemplate': _plantillaNombre(l10n.alarmMissedNotificationText),
       });
     } catch (e) {
       debugPrint('[PluriWave][alarmas] setNotificationStrings ERROR $e');
@@ -209,6 +258,14 @@ class ServicioAlarmasAndroid implements PuertoAlarmasAndroid {
     return traducir(sentinel).replaceFirst(sentinel.toString(), '{minutes}');
   }
 
+  /// Same sentinel-swap approach as [_plantillaMinutos], but for a
+  /// `{String} -> String` message: swaps a unique sentinel token back for the
+  /// literal `{name}` placeholder Kotlin fills in at fire time.
+  static String _plantillaNombre(String Function(Object) traducir) {
+    const sentinel = 'PLURIWAVE_NAME_SENTINEL';
+    return traducir(sentinel).replaceFirst(sentinel, '{name}');
+  }
+
   @override
   Stream<EventoAlarmaAndroid> get eventosAlarma => _eventosController.stream;
 
@@ -286,10 +343,43 @@ class ServicioAlarmasAndroid implements PuertoAlarmasAndroid {
   Future<void> ocultarNotificacionAlarma(String alarmaId) =>
       _logAndInvokeVoid('dismissAlarmNotification', {'id': alarmaId});
 
+  @override
+  Future<void> ocultarSoloNotificacion(String alarmaId) =>
+      _logAndInvokeVoid('dismissAlarmNotificationOnly', {'id': alarmaId});
+
   @override
   Future<void> detenerSonidoNativo(String alarmaId) =>
       _logAndInvokeVoid('stopNativeAlarmSound', {'id': alarmaId});
 
+  @override
+  Future<String?> alarmaSonandoId() async {
+    try {
+      return await _channel.invokeMethod<String>('getActiveRingingAlarmId');
+    } catch (e) {
+      // Fail-toward-silence (Finding 2): a query failure must NOT be
+      // mistaken for "nothing is ringing" by callers like
+      // EstadoAlarmas._detenerSiEstaSonando, which would otherwise skip the
+      // stop entirely on a genuinely ringing alarm. Rethrow so the caller can
+      // fall back to the id-scoped legacy stop instead.
+      debugPrint('[PluriWave][alarmas] alarmaSonandoId ERROR $e');
+      rethrow;
+    }
+  }
+
+  @override
+  Future<ResultadoDetencion> detenerSonidoActivo() async {
+    try {
+      final raw = await _channel.invokeMethod<Map<Object?, Object?>>(
+        'stopActiveAlarm',
+      );
+      if (raw == null) return ResultadoDetencion.fallo;
+      return ResultadoDetencion.fromMap(raw);
+    } catch (e) {
+      debugPrint('[PluriWave][alarmas] detenerSonidoActivo ERROR $e');
+      return ResultadoDetencion.fallo;
+    }
+  }
+
   @override
   Future<bool> solicitarPermisoAlarmasExactas() async {
     final abierto = await _channel.invokeMethod<bool>(