shikhaRRCode/Urban-Lane-Backend ? reverse-engineered prompt

Build me the backend for a ShopNow style online store, where customers can sign up, log in, browse products, add items to cart, place orders, and track them. I also need separate seller and admin access, so sellers can manage their products and admins can oversee the whole platform. Make the app use secure login with token based authentication, support product images, and save all the usual ecommerce data like users, products, cart items, orders, and order status in a database.

Please set it up as a clean REST API with sensible routes, middleware for protecting pages, and basic validation and error handling. Use MongoDB for storage and keep the code organized so it is easy to expand later. If you need to check current docs for anything, go ahead and look them up online.