{"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-8fgq0t4x","versions":[{"created_at":"2026-06-10T17:56:44Z","element_count":73,"note":"5軸GA polish 58->97 by M5 (autonomous)","saved_by":"mcp","sha256":"07dd01408bb00b5fbb5a4cfcccca191a842ac18452ff37f842f514e1fb98a029","version":3}]}