{"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-u4vdqo5w","versions":[{"created_at":"2026-06-10T18:29:56Z","element_count":74,"note":"5軸GA polish 56->97 by M5 (autonomous)","saved_by":"mcp","sha256":"095fa3acfaa08bd734e771e13ed11fe59830a1cab8b91e3859c75bb1675b3446","version":3}]}