dsh-wait-subagent

Active wait for background continuable subagents in DeepSeek Harness: registers a wait_subagent tool that blocks until the named subagent settles, then returns its stop reason and closing message — closing the gap between run_in_background fire-and-return and the async settlement notice. dsh-wait-subagent：为 DeepSeek Harness 提供后台 continuable 子代理的主动等待——注册 wait_subagent 工具阻塞至目标子代理收尾，返回停止原因与收尾消息，补齐后台子代理只能被动等通知的缺口。