{"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-egd9z6e9","versions":[{"created_at":"2026-06-10T16:23:22Z","element_count":90,"note":"5軸GA polish 60->98 by M5 (autonomous)","saved_by":"mcp","sha256":"14b610871379661980621e903e0238bdff9deafbfcac2aaa5bf5996b10f9fb45","version":2}]}