broker-auth

Platform account binding for C2C resale. Use when the user needs to authorize Claude to act on their behalf on resale platforms (Xianyu/闲鱼, Zhuanzhuan/转转, eBay, Depop). Opens a browser for one-time login; session cookies are persisted to disk and reused until expiry. Trigger: "bind account", "authorize", "login to Xianyu", "connect my account". Also invoke before broker-price and broker-card when no valid session…