{"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-1bih7iia","versions":[{"created_at":"2026-06-10T15:53:07Z","element_count":84,"note":"5軸GA polish 60->98 by M5 (autonomous)","saved_by":"mcp","sha256":"782b81d7487f5505b3d521ea625841f2cb25b2ce811651dcc3143ed292e51706","version":4}]}