{"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-eng2j2og","versions":[{"created_at":"2026-06-10T15:37:09Z","element_count":71,"note":"5軸GA polish 53->97 by M5 (autonomous)","saved_by":"mcp","sha256":"71be6afae124d343701716ce41c7ee07dadf5720a816153411ce270eca4a040d","version":4}]}