{"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-7m3j5x1y","versions":[{"created_at":"2026-06-10T07:41:56Z","element_count":91,"note":"5軸GA polish 54->98 by M5 (autonomous)","saved_by":"mcp","sha256":"98728276e0137a7b54565bbfbfef4bc8624da414fee76e4f39ebc2f2fd1ddfc0","version":2}]}