refactor: common message dialog method

ui/flutter/lib/core/common/libgopeed_channel.dart

@@ -1,6 +1,7 @@
 import 'dart:convert';
 
 import 'package:flutter/services.dart';
+
 import 'libgopeed_interface.dart';
 import 'start_config.dart';
 

ui/flutter/lib/core/common/libgopeed_ffi.dart

@@ -3,8 +3,8 @@ import 'dart:convert';
 import 'dart:ffi';
 
 import 'package:ffi/ffi.dart';
-import '../ffi/libgopeed_bind.dart';
 
+import '../ffi/libgopeed_bind.dart';
 import 'libgopeed_interface.dart';
 import 'start_config.dart';
 

ui/flutter/lib/core/entry/libgopeed_boot_browser.dart

@@ -1,6 +1,6 @@
 import 'dart:async';
 
-import 'package:gopeed/core/common/start_config.dart';
+import '../common/start_config.dart';
 
 import '../libgopeed_boot.dart';