Fix cached reminder recovery and retain pre-reconcile idle diagnostics

mobile/lib/services/local_notification_service.dart

@@ -34,6 +34,7 @@ class ReminderRequest {
 abstract class ReminderGateway {
   Future<ReminderPermissions> permissions({required bool request});
   Future<Set<int>> pendingIds();
+  Future<Set<int>> missingSystemIds(Set<int> ids) async => {};
   Future<Set<int>> ownedIds() => pendingIds();
   Future<String> sendTestReminder({required bool scheduled}) async =>
       '当前环境不支持通知测试';
@@ -124,6 +125,8 @@ class LocalNotificationService extends NotificationService {
       );
     }
     final pending = await gateway.pendingIds();
+    // Include overdue entries so warm-resume diagnostics survive their removal.
+    final missing = await gateway.missingSystemIds(pending);
     for (final old in (await gateway.ownedIds()).difference(
       desired.keys.toSet(),
     )) {
@@ -135,6 +138,7 @@ class LocalNotificationService extends NotificationService {
       final fingerprint =
           '${request.fireAt.millisecondsSinceEpoch}/${request.title}/${request.body}/${request.exact}';
       if (pending.contains(entry.key) &&
+          !missing.contains(entry.key) &&
           _fingerprints[entry.key] == fingerprint) {
         continue;
       }
@@ -297,6 +301,20 @@ class PluginReminderGateway extends ReminderGateway {
     return owned;
   }
 
+  @override
+  Future<Set<int>> missingSystemIds(Set<int> ids) async {
+    if (ids.isEmpty) return {};
+    try {
+      final missing = await _system
+          .invokeListMethod<int>('findMissingAlarmHandles', ids.toList())
+          .timeout(const Duration(seconds: 2));
+      return missing?.where(ids.contains).toSet() ?? {};
+    } catch (_) {
+      // Availability of this extra check must not block normal scheduling.
+      return {};
+    }
+  }
+
   @override
   Future<String> sendTestReminder({required bool scheduled}) async {
     final access = await permissions(request: false);