feat: ui improvement

flutter 3.7 compatibility
responsive view
beautiful progress bar
select file in treeview
downlading and downloaded page

ui/flutter/README.md

@@ -1,16 +1,5 @@
-# gopeed
 
-A new Flutter project.
 
-## Getting Started
 
-This project is a starting point for a Flutter application.
 
-A few resources to get you started if this is your first Flutter project:
-
-- [Lab: Write your first Flutter app](https://docs.flutter.dev/get-started/codelab)
-- [Cookbook: Useful Flutter samples](https://docs.flutter.dev/cookbook)
-
-For help getting started with Flutter development, view the
-[online documentation](https://docs.flutter.dev/), which offers tutorials,
-samples, guidance on mobile development, and a full API reference.
+Don't forget to run`dart format .`before you commit to keep your code in standard dart format