{"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-ur5zs2tz","versions":[{"created_at":"2026-06-10T13:32:56Z","element_count":77,"note":"backfill: 延床=居室床スラブ実面積74.1㎡(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":"458f4e9196896f74f83211f96df8ef8438ef7f7ddaf4da0289dfd2714d9e6054","version":7},{"created_at":"2026-06-10T12:16:03Z","element_count":89,"note":"5軸GA polish 56->98 by M5 (autonomous)","saved_by":"mcp","sha256":"92715c7427574b926cdbcf7cf74c852c4844472fa1f2d516e6a90958a341e81c","version":3}]}