{"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-v16mhoia","versions":[{"created_at":"2026-06-10T18:29:55Z","element_count":83,"note":"5軸GA polish 61->98 by M5 (autonomous)","saved_by":"mcp","sha256":"bf3f1182fdb4d4f97eb12005840628f3d9495d202a7d99ba1a642e75e2dd65f3","version":3}]}