{"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-1uym9639","versions":[{"created_at":"2026-06-10T07:42:29Z","element_count":85,"note":"5軸GA polish 61->98 by M5 (autonomous)","saved_by":"mcp","sha256":"819c7c20c0ddca86034f39041e423846d8b459b468f36d3d2d96d57447fc12bb","version":2}]}