{"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-p2ym1m42","versions":[{"created_at":"2026-06-10T14:46:00Z","element_count":84,"note":"5軸GA polish 58->98 by M5 (autonomous)","saved_by":"mcp","sha256":"23f3eb6a5a365cf100925b849418d8a7a5e2ad96bd917a32fc2951bb64736009","version":6}]}