{"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-06r0gil0","versions":[{"created_at":"2026-06-10T18:29:56Z","element_count":84,"note":"5軸GA polish 60->98 by M5 (autonomous)","saved_by":"mcp","sha256":"a533c00f44b56b6d9f9fde09cbb5f7f4be0d82ecb898ca45ecb895bd00a6fbce","version":3}]}