{"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-w6huba80","versions":[{"created_at":"2026-06-12T09:21:31Z","element_count":134,"note":"言葉から生成: 平屋(矩形) / ロフト付きワンルーム・吹抜・大開口 / ロフト付き / 吹抜 / 大開口","saved_by":"mcp:create","sha256":"","version":1}]}