{"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-yxsc8y9b","versions":[{"created_at":"2026-06-10T18:46:37Z","element_count":84,"note":"5軸GA polish 61->97 by M5 (autonomous)","saved_by":"mcp","sha256":"3cf6d6c2c38578a1b0679998a78620cffef598414af4c34cb818d613414c6995","version":3}]}