{"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-6ybenxu5","versions":[{"created_at":"2026-06-10T14:29:50Z","element_count":85,"note":"5軸GA polish 56->97 by M5 (autonomous)","saved_by":"mcp","sha256":"01b84874c9dae932bc4d4cd3661184638b3f978aa4a136108f2042ef8b3245c1","version":7}]}