{"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-rh7e8ia8","versions":[{"created_at":"2026-06-10T17:40:01Z","element_count":71,"note":"5軸GA polish 61->96 by M5 (autonomous)","saved_by":"mcp","sha256":"0afcf6dc9188933639e90d591eca8358265de35075b0525f2234496d989242e6","version":3}]}