{
  "step_id": 447,
  "complete": false,
  "success": null,
  "truncated": false,
  "reason": "仿真进程发生 access violation；随后 RPC 连接中断（WinError 10054）",
  "wall_seconds": 2282.332008123398,
  "wall_time_source": "估算：首条计时事件还原起点至 failure.json 修改时间",
  "derived_from_failure": true,
  "valid_for_success_rate": false
}