{"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-9fizk2c2","versions":[{"created_at":"2026-06-10T15:53:05Z","element_count":84,"note":"5軸GA polish 60->98 by M5 (autonomous)","saved_by":"mcp","sha256":"272f0ac70dc703741383eb61b511a692ec21f699752df21509c9e0ceb504654c","version":4}]}