{"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-m2d61t3k","versions":[{"created_at":"2026-06-10T14:29:38Z","element_count":72,"note":"5軸GA polish 60->97 by M5 (autonomous)","saved_by":"mcp","sha256":"ac3def35b2dce9f8abc55cad3ec89b3f37493e0463fb4b36aceb21a9fd352484","version":7}]}