{"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-g70bdp3l","versions":[{"created_at":"2026-07-08T20:45:00Z","element_count":168,"note":"言葉から生成: 総2階(箱) / ピアノ室と防音・吹抜のある家","saved_by":"mcp:create","sha256":"","version":1}]}