feat(coding-runtime): add managed Pi extension host

electron/coding-runtime/pi/worker-process.ts

@@ -75,7 +75,7 @@ export function buildPiRpcArgs(
     '--no-themes',
     '--no-context-files',
     '--no-approve',
-    '--no-tools',
+    '--tools', 'read,bash,edit,write,grep,find,ls,ask_user',
     ...additionalArgs,
   ];
 }
@@ -310,6 +310,17 @@ export class PiWorkerProcess {
     return this.rpc.request<T>(command, options);
   }
 
+  send(command: PiRpcCommand): Promise<void> {
+    if (!this.rpc) {
+      return Promise.reject(new PiProcessError(
+        'PI_WORKER_START_FAILED',
+        'Pi worker has not started',
+        { generation: this.generationValue },
+      ));
+    }
+    return this.rpc.send(command);
+  }
+
   subscribe(listener: (event: PiRpcEvent) => void): () => void {
     if (!this.rpc) throw new Error('Pi worker has not started');
     return this.rpc.subscribe(listener);