{"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-pjcpu70y","versions":[{"created_at":"2026-06-10T15:37:00Z","element_count":72,"note":"5軸GA polish 60->97 by M5 (autonomous)","saved_by":"mcp","sha256":"6feef45a1341f7b2dde231fe69faca2a125bee6e801071df2ffce768ddc93be3","version":4}]}