{"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-m4evv10i","versions":[{"created_at":"2026-06-10T18:29:53Z","element_count":84,"note":"5軸GA polish 60->98 by M5 (autonomous)","saved_by":"mcp","sha256":"ac2f20ebad1dbdd0f0f8714eff0823ef8e41ebf114bb0038cc59902ac41c38dd","version":3}]}