fix: 修复ws相关逻辑

frontend/electron/main.ts

@@ -537,6 +537,10 @@ ipcMain.handle('start-backend', async () => {
   return startBackend(appRoot)
 })
 
+ipcMain.handle('stop-backend', async () => {
+  return stopBackend()
+})
+
 // Git相关
 ipcMain.handle('download-git', async () => {
   const appRoot = getAppRoot()

frontend/electron/preload.ts

@@ -26,6 +26,7 @@ contextBridge.exposeInMainWorld('electronAPI', {
   cloneBackend: (repoUrl?: string) => ipcRenderer.invoke('clone-backend', repoUrl),
   updateBackend: (repoUrl?: string) => ipcRenderer.invoke('update-backend', repoUrl),
   startBackend: () => ipcRenderer.invoke('start-backend'),
+  stopBackend: () => ipcRenderer.invoke('stop-backend'),
 
   // 管理员权限相关
   checkAdmin: () => ipcRenderer.invoke('check-admin'),