fix: start background service from FCM handler when service is dead

lib/background/background.dart

@@ -22,13 +22,19 @@ Future<void> serviceMain(ServiceInstance service) async {
 
   final Map<String, Map<String, dynamic>> activeSubscriptions = {};
   final nostrService = NostrService();
-  final db = await openMostroDatabase('events.db');
-  final eventStore = EventStorage(db: db);
 
+  // Register event handlers BEFORE awaiting database open to avoid
+  // losing events (e.g. 'start' invoked by FCM handler during db init).
   service.on('app-foreground-status').listen((data) {
     isAppForeground = data?['is-foreground'] ?? isAppForeground;
   });
 
+  service.on('fcm-wake').listen((data) {
+    // Service is already running with active subscriptions.
+    // Nostr subscriptions will automatically receive new events.
+    logger?.d('FCM wake signal received - subscriptions already active');
+  });
+
   service.on('start').listen((data) async {
     if (data == null) return;
 
@@ -50,6 +56,9 @@ Future<void> serviceMain(ServiceInstance service) async {
     service.invoke('service-ready', {});
   });
 
+  final db = await openMostroDatabase('events.db');
+  final eventStore = EventStorage(db: db);
+
   service.on('update-settings').listen((data) async {
     if (data == null) return;
 

lib/services/fcm_service.dart

@@ -1,9 +1,11 @@
 import 'dart:async';
+import 'dart:convert';
 import 'dart:io';
 import 'package:firebase_core/firebase_core.dart';
 import 'package:firebase_messaging/firebase_messaging.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter_background_service/flutter_background_service.dart';
+import 'package:mostro_mobile/data/models/enums/storage_keys.dart';
 import 'package:mostro_mobile/services/logger_service.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 import 'package:mostro_mobile/firebase_options.dart';
@@ -45,8 +47,39 @@ Future<void> firebaseMessagingBackgroundHandler(RemoteMessage message) async {
       final service = FlutterBackgroundService();
       final isRunning = await service.isRunning();
 
-      if (!isRunning) {
+      if (isRunning) {
+        // Service is already running — signal it that FCM detected new activity
+        service.invoke('fcm-wake', {});
+      } else {
+        // Service is dead — start it and send settings
         await sharedPrefs.setBool('fcm.pending_fetch', true);
+        await service.startService();
+
+        final settingsJson = await sharedPrefs.getString(
+          SharedPreferencesKeys.appSettings.value,
+        );
+        if (settingsJson != null) {
+          Map<String, dynamic>? settings;
+          try {
+            settings = jsonDecode(settingsJson) as Map<String, dynamic>?;
+          } catch (e) {
+            debugPrint('FCM: Failed to decode settings: $e');
+          }
+
+          // Wait briefly for service to initialize (FCM handlers must complete quickly)
+          const maxWait = Duration(seconds: 3);
+          final deadline = DateTime.now().add(maxWait);
+          while (!(await service.isRunning())) {
+            if (DateTime.now().isAfter(deadline)) break;
+            await Future.delayed(const Duration(milliseconds: 100));
+          }
+
+          if (await service.isRunning() && settings != null) {
+            service.invoke('start', {
+              'settings': settings,
+            });
+          }
+        }
       }
     } catch (e) {
       debugPrint('FCM: background service error: $e');