fix foreground service and add notification nav

wraps MaterialApp in WithForegroundService to keep alive when swiped away

persists last connected device and clears on manual disconnect to allow
reconnect after kill

added lifecycle tracking to iOS and keep android notification alive with
heartbeat

add notification navigation

change screen tests to be less brittle

address PR commnets

lib/connector/meshcore_connector.dart

@@ -40,6 +40,7 @@ import '../storage/contact_settings_store.dart';
 import '../storage/contact_store.dart';
 import '../storage/message_store.dart';
 import '../storage/unread_store.dart';
+import '../storage/last_device_store.dart';
 import '../utils/app_logger.dart';
 import '../utils/battery_utils.dart';
 import '../utils/platform_info.dart';
@@ -281,6 +282,7 @@ class MeshCoreConnector extends ChangeNotifier {
   final ContactDiscoveryStore _discoveryContactStore = ContactDiscoveryStore();
   final ChannelStore _channelStore = ChannelStore();
   final UnreadStore _unreadStore = UnreadStore();
+  final LastDeviceStore _lastDeviceStore = LastDeviceStore();
   List<Channel> _cachedChannels = [];
   final Map<int, bool> _channelSmazEnabled = {};
   bool _lastSentWasCliCommand =
@@ -768,6 +770,10 @@ class MeshCoreConnector extends ChangeNotifier {
     _appDebugLogService = appDebugLogService;
     _backgroundService = backgroundService;
     _timeoutPredictionService = timeoutPredictionService;
+
+    // When the app resumes from background, check if we need to reconnect.
+    _backgroundService?.onResume = _onAppResumed;
+
     _usbManager.setDebugLogService(_appDebugLogService);
     _tcpConnector.setDebugLogService(_appDebugLogService);
 
@@ -1879,6 +1885,7 @@ class MeshCoreConnector extends ChangeNotifier {
       );
 
       _setState(MeshCoreConnectionState.connected);
+      _lastDeviceStore.persistLastDevice(_deviceId!, _deviceDisplayName!);
       if (_shouldGateInitialChannelSync) {
         _hasReceivedDeviceInfo = false;
         _pendingInitialChannelSync = true;
@@ -2225,6 +2232,56 @@ class MeshCoreConnector extends ChangeNotifier {
     });
   }
 
+  /// Called by [BackgroundService] when the app returns to the foreground.
+  /// If the BLE connection was lost while backgrounded, this kicks off an
+  /// immediate reconnect attempt instead of waiting for the next timer tick.
+  void _onAppResumed() {
+    if (_shouldAutoReconnect &&
+        _state != MeshCoreConnectionState.connected &&
+        _state != MeshCoreConnectionState.connecting) {
+      _appDebugLogService?.info(
+        'App resumed – triggering reconnect check',
+        tag: 'Lifecycle',
+      );
+      _cancelReconnectTimer();
+      _scheduleReconnect();
+    } else if (_state == MeshCoreConnectionState.disconnected &&
+        _lastDeviceId == null) {
+      // App was fully restarted (swiped away).  Try to restore from prefs.
+      tryAutoReconnect();
+    }
+  }
+
+  /// Attempt to reconnect to the last persisted BLE device.
+  ///
+  /// Called on fresh app start (after a swipe-away kill) so the user is
+  /// brought straight back to the connected state instead of the scan screen.
+  Future<bool> tryAutoReconnect() async {
+    if (_state == MeshCoreConnectionState.connecting ||
+        _state == MeshCoreConnectionState.connected) {
+      return false;
+    }
+    final deviceId = _lastDeviceStore.getPersistedDeviceId();
+    if (deviceId!.isEmpty) {
+      return false;
+    }
+
+    final displayName = _lastDeviceStore.getPersistedDeviceName();
+    _appDebugLogService?.info(
+      'Auto-reconnecting to $deviceId ($displayName)',
+      tag: 'Lifecycle',
+    );
+
+    try {
+      final device = BluetoothDevice.fromId(deviceId);
+      await connect(device, displayName: displayName);
+      return true;
+    } catch (e) {
+      _appDebugLogService?.error('Auto-reconnect failed: $e', tag: 'Lifecycle');
+      return false;
+    }
+  }
+
   Future<void> disconnect({
     bool manual = true,
     bool skipBleDeviceDisconnect = false,
@@ -2245,6 +2302,8 @@ class MeshCoreConnector extends ChangeNotifier {
     if (manual) {
       _manualDisconnect = true;
       _cancelReconnectTimer();
+      _lastDeviceStore.clearPersistedDevice();
+      _notificationService.cancelAll();
       unawaited(_backgroundService?.stop());
     } else {
       _manualDisconnect = false;
@@ -4910,6 +4969,17 @@ class MeshCoreConnector extends ChangeNotifier {
         );
   }
 
+  /// Public accessor to find a channel by its index.
+  Channel? findChannelByIndex(int index) => _findChannelByIndex(index);
+
+  /// Find a contact by its public key hex string.
+  Contact? findContactByKeyHex(String keyHex) {
+    return _contacts.cast<Contact?>().firstWhere(
+      (c) => c?.publicKeyHex == keyHex,
+      orElse: () => null,
+    );
+  }
+
   void _maybeIncrementChannelUnread(
     ChannelMessage message, {
     required bool isNew,