fix: fix disconnect when selecting firmware for dfu

lib/controller/bluetooth.dart

@@ -14,6 +14,13 @@ part 'bluetooth.g.dart';
 
 final log = Logger('BluetoothController');
 
+final backgroundBluetoothDisconnectSuppressionCountProvider =
+    StateProvider<int>((ref) => 0);
+
+final backgroundBluetoothDisconnectSuppressedProvider = Provider<bool>((ref) {
+  return ref.watch(backgroundBluetoothDisconnectSuppressionCountProvider) > 0;
+});
+
 @Riverpod(keepAlive: true)
 FlutterReactiveBle reactiveBle(Ref ref) {
   ref.keepAlive();