New features of the folder manager:
- ✅ Drag-and-drop folder system, supporting 2-level nesting
- ✅ Automatically detects 9 types of Gems and displays dedicated icons
- ✅ Double-click rename dialog function
文件夹管理器新功能：
- ✅ 拖放式文件夹系统，支持 2 级嵌套
- ✅ 自动检测 9 种 Gem 类型并显示专属图标
- ✅ 双击重命名对话功能