{"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-6er2qdj4","versions":[{"created_at":"2026-06-10T17:56:31Z","element_count":84,"note":"5軸GA polish 61->98 by M5 (autonomous)","saved_by":"mcp","sha256":"74f6c0d59b54640fc5000a3eb1e80e500fe19682163dd1ef8d51ed7bc64a7be5","version":3}]}