{"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-xtbd2az4","versions":[{"created_at":"2026-06-10T15:19:42Z","element_count":85,"note":"5軸GA polish 60->98 by M5 (autonomous)","saved_by":"mcp","sha256":"ab3bd7b10ec51ae54147bca7306b4bafb779b7a68e734a8fa8108e95b8755936","version":5}]}