重构: 连接切换链收敛与代码清理

- 切换连接统一switchConnection入口，删watcher与抑制机制
- 删除活跃服务器后回落本地并加载
- 侧边栏与指示器点击统一上抛，重复点击可刷新
- Wails事件解析归一，查重谓词抽公共
- 删空壳别名文件与过期文档截图

frontend/src/components/UpdateNotification.vue

@@ -8,6 +8,7 @@ import { Modal, Message, Progress } from '@arco-design/web-vue'
 import { useUpdateStore } from '../stores/update'
 import { parseMarkdown, isMarkedReady, preloadMarked } from '../utils/markedExtensions'
 import { sanitizeHtml } from '@/utils/fileUtils'
+import { parseWailsEventData } from '@/utils/wailsEvent'
 import { DownloadUpdate } from '../wailsjs/v3-bindings/u-desk/app'
 import { On, Off } from '@wailsio/events'
 
@@ -292,7 +293,7 @@ const handleDownload = async () => {
 
 // 下载完成处理（本地覆盖：关闭弹窗）
 const onDownloadComplete = async (event) => {
-  const data = typeof event === 'string' ? JSON.parse(event) : event
+  const data = parseWailsEventData(event)
 
   if (data.error) {
     closeProgressModal()