{"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-j899h0o5","versions":[{"created_at":"2026-06-10T18:29:58Z","element_count":74,"note":"5軸GA polish 54->97 by M5 (autonomous)","saved_by":"mcp","sha256":"db9178f4f781e0d2e85ce44d253ca4ce7ecf69519785038aa656b94b52cdf016","version":3}]}