refine UIs for beneficials for different membership (based on different NFTs)

[bobjiang]

There are several things required to improve:

1. show the promoted price, for example, the normal price is $69.90, and promoted price is $39.90 for membership.
2. add a link for how to get membership (a link to request token) on demo page (like fashion, music or car)
3. add a cart feature, and in the cart, show the discount for membership

tbh, I didn't get the core of brand connector although I know what it is. https://brandconnector.tokenscript.org/

please have one end-2-end use case for the brand connector. (Now it is like partial e-commercial feature)