{"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-0u6zji2g","versions":[{"created_at":"2026-06-18T14:00:05Z","element_count":173,"note":"言葉から生成: 総2階(箱) / 茶室と縁側のある和の住まい","saved_by":"mcp:create","sha256":"","version":1}]}