Show the seller's brand on the home product cards, like the design:
a small logo circle + name overlaid above the title.
- new SellerChip component: renders nothing without a name; falls back to
the seller's initial when no logo is present (e.g. before the backend
ships seller_logo). seller_name is already returned today, so the name
shows immediately.
- thread sellerName/sellerLogo/sellerUsername through ProductHomepage type,
the home discounts + for-you mappings, and the MondrianProductList /
HorizontalProductList card interfaces + overlays.
Only renders where seller data is mapped (home), so seller-page and
store-dashboard tiles are unaffected.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>