merge: integrate agent server sleep restart

electron/coding-runtime/pi/agent-server-process.ts

@@ -490,6 +490,7 @@ export class PiAgentServerProcess {
   }
 
   start(): Promise<void> {
+    if (this.stopFlight) return this.stopFlight.then(() => this.start());
     if (this.startFlight) return this.startFlight;
     if (this.child && !this.failure) return Promise.resolve();
     this.startFlight = this.startServer().finally(() => {