{"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-ixdr7y5x","versions":[{"created_at":"2026-08-04T11:49:07Z","element_count":253,"note":"言葉から生成: 中庭ロの字 / 狭小の町家・吹抜・坪庭 / 吹抜 / 坪庭 / 高断熱仕様 / 雪下ろし補強 / 隣地境界採光確保","saved_by":"mcp:create","sha256":"","version":1}]}