{"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-l06uvsom","versions":[{"created_at":"2026-06-10T07:59:11Z","element_count":85,"note":"5軸GA polish 61->98 by M5 (autonomous)","saved_by":"mcp","sha256":"ef8c4d982d2aec0b3ad45a2a89abcefc7bede32c1412b1824d7ad219bb7fa3e3","version":2}]}