{"note":"bim_versions 導入後の保存のみ記録 (それ以前は bim_canonical 上書きで履歴なし)","ok":true,"slug":"u-house-x6g71fpy","versions":[{"created_at":"2026-06-10T15:53:07Z","element_count":91,"note":"5軸GA polish 61->98 by M5 (autonomous)","saved_by":"mcp","sha256":"894782f769e7844f9b5608b9018358fa55fd4c15d668a25ba0ef6cf440085392","version":4}]}