新增: 自动升级体系 + WorkerW重建检测 + 知识卡片优化

自动升级:
- 版本变量注入 (-ldflags -X main.version)
- 远程 version.json 检查 + 弹窗提示(非强制右下角/强制居中)
- updater.exe 嵌入主程序, 运行时释放到临时目录
- 下载+SHA256校验+备份+替换+回滚 全流程
- 托盘菜单"检查更新"

稳定性:
- WorkerW 重建自动检测(每10s)并重新嵌入
- 左键托盘点击防抖
- 设置窗口已打开时正确前置

优化:
- 知识卡片prompt改为面向开发者的硬核内容
- 配置目录统一到 ~/.u-desktop/
- 设置窗口WebView2数据目录改为configDir下

win32.go

@@ -29,6 +29,7 @@ var (
 	procPostMessageW        = user32.NewProc("PostMessageW")
 	procTranslateMessage    = user32.NewProc("TranslateMessage")
 	procDispatchMessageW    = user32.NewProc("DispatchMessageW")
+	procGetParent           = user32.NewProc("GetParent")
 )
 
 var wv webview2.WebView
@@ -42,12 +43,19 @@ const (
 )
 
 const (
-	gwlStyle  = uintptr(0xFFFFFFF0) // GWL_STYLE = -16
-	wsPopup   = uintptr(0x80000000)
-	wsVisible = uintptr(0x10000000)
-	wsChild   = uintptr(0x02000000)
-	wsSizebox = uintptr(0x00040000)
-	wsMaxbox  = uintptr(0x00010000)
+	gwlStyle   = uintptr(0xFFFFFFF0) // GWL_STYLE = -16
+	gwlExStyle = uintptr(0xFFFFFFFEC) // GWL_EXSTYLE = -20
+	wsPopup    = uintptr(0x80000000)
+	wsVisible  = uintptr(0x10000000)
+	wsChild    = uintptr(0x02000000)
+	wsSizebox  = uintptr(0x00040000)
+	wsMaxbox   = uintptr(0x00010000)
+)
+
+const (
+	wsExTransparent = uintptr(0x00000020)
+	wsExLayered     = uintptr(0x00080000)
+	wsExToolwindow  = uintptr(0x00000080)
 )
 
 var htmlQueue = make(chan string, 1)