{"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-5c9257k9","versions":[{"created_at":"2026-06-17T07:13:01Z","element_count":122,"note":"言葉から生成: 平屋(矩形) / 平屋の別荘・大きな軒・土間 / 吹放し空間 / 2.4mの深さの軒 / 24時間換気2種 / 積雪420mm対応屋根勾配45度 / 耐震等級3","saved_by":"mcp:create","sha256":"","version":1}]}