{"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-sprowstoncrescenthou-sblwtnh2","versions":[{"created_at":"2026-06-10T13:20:06Z","element_count":63,"note":"backfill: 延床=居室床スラブ実面積93.5㎡(基礎/屋外/ロフト除外)。設備数量/コスト過大の是正","saved_by":"mcp","sha256":"5a409fb92c414bd7de6c5da26b38734488d42cd9398d588d3ac915da9cd2d79e","version":10},{"created_at":"2026-06-10T10:23:02Z","element_count":74,"note":"5軸GA polish 43->97 by M5 (autonomous)","saved_by":"mcp","sha256":"5500398f97174bdf659f2a77609a9e9133f3619e41b3e22575eb1fab9c547ecd","version":2}]}