{"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-willowcreekbungalow-kfyecj7q","versions":[{"created_at":"2026-06-10T13:23:15Z","element_count":66,"note":"backfill: 延床=居室床スラブ実面積90.0㎡(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":"7afbf966b2709aa97e477be0cacebaea1107d0c46280873af0abdb89ddd1bc9d","version":10},{"created_at":"2026-06-10T10:37:48Z","element_count":84,"note":"5軸GA polish 43->98 by M5 (autonomous)","saved_by":"mcp","sha256":"e4ea963e280921fff973ce260edbd9b74ddd9b52bef725e1dc446471e35bf016","version":2}]}