{"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-r6f0oj8r","versions":[{"created_at":"2026-06-10T17:56:39Z","element_count":83,"note":"5軸GA polish 53->98 by M5 (autonomous)","saved_by":"mcp","sha256":"e0e07879ba86c34855381f95f5844020636d8e12b3ed38036048593f30381c54","version":3}]}