{"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-gh5e5cp9","versions":[{"created_at":"2026-06-10T16:38:57Z","element_count":83,"note":"5軸GA polish 56->98 by M5 (autonomous)","saved_by":"mcp","sha256":"67a12e2ff5433514dc89e65e3ba8979d8879a39dd3e0bb32dfaf80ba398d68eb","version":2}]}