{"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-n59fr4t4","versions":[{"created_at":"2026-06-10T18:46:54Z","element_count":90,"note":"5軸GA polish 61->97 by M5 (autonomous)","saved_by":"mcp","sha256":"713bb2d18456c34b6d83b8012927dbab089637dbf40084de2e298d2bf93f45e4","version":3}]}