{"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-vlb0s5v9","versions":[{"created_at":"2026-06-10T17:56:45Z","element_count":73,"note":"5軸GA polish 54->96 by M5 (autonomous)","saved_by":"mcp","sha256":"e93d8ace89206bb9a02cf7c5ee2b25cdf29eae406d76793cd47a2f96cf83cafe","version":3}]}