devex: Enable Electron MCP servers with DevTools debug port (#25795)

packages/desktop-electron/src/main/index.ts

@@ -74,6 +74,7 @@ setupApp()
 function setupApp() {
   ensureLoopbackNoProxy()
   app.commandLine.appendSwitch("proxy-bypass-list", "<-loopback>")
+  if (!app.isPackaged) app.commandLine.appendSwitch("remote-debugging-port", "9222")
 
   if (!app.requestSingleInstanceLock()) {
     app.quit()