{"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-pv3lr1i0","versions":[{"created_at":"2026-06-10T18:46:54Z","element_count":72,"note":"5軸GA polish 61->97 by M5 (autonomous)","saved_by":"mcp","sha256":"ff587b7aa86510ed117552c30a347a86a07860ea2977e603f6b271458a0e0c17","version":3}]}