{"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-c1jir6yb","versions":[{"created_at":"2026-06-10T07:59:20Z","element_count":84,"note":"5軸GA polish 61->98 by M5 (autonomous)","saved_by":"mcp","sha256":"95570746f1b49cfc180f127e37daed4e1702100474d337a3c3adbf9c41d337c8","version":2}]}