{"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-ch4etkma","versions":[{"created_at":"2026-06-10T15:53:05Z","element_count":88,"note":"5軸GA polish 56->98 by M5 (autonomous)","saved_by":"mcp","sha256":"e225e548e22a210a20ee4972b143011017074e6609478d4319bcce9361dd752f","version":3}]}