{"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-7z1a9ivm","versions":[{"created_at":"2026-06-10T18:13:51Z","element_count":91,"note":"5軸GA polish 54->98 by M5 (autonomous)","saved_by":"mcp","sha256":"a14872c49ebd08e0950018c42d71e111e90a4fd418db71f2a5d7af03751cb162","version":3}]}