{"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-ff40a4kb","versions":[{"created_at":"2026-06-10T13:55:49Z","element_count":72,"note":"5軸GA polish 66->97 by M5 (autonomous)","saved_by":"mcp","sha256":"da053521fd3ce8f08757d1e0777ec2f22cd7b050b08d36d331bb3e8c56e0afdc","version":5},{"created_at":"2026-06-10T13:46:47Z","element_count":54,"note":"backfill: 延床=居室床スラブ実面積78.3㎡(基礎/屋外/ロフト除外)。設備数量/コスト過大の是正","saved_by":"mcp","sha256":"d3b781dbf261af8f29f2867992bd83db73d4bceeab2e7bf743a12a174545f6d9","version":4}]}