feat(search/explore): home-style product tiles with seller brand chip

Bring the home product tile to search and explore: seller brand chip
(SellerChip) plus price/discount overlay, instead of a bare image.

- search: map discountPercent/discountPrice/basePrice + sellerName from
  ProductSearchResult (sellerName is already returned, so the chip shows
  now with the initial-letter fallback).
- explore: map sellerName/sellerLogo/sellerUsername (and add them to the
  Product type); these populate once the backend ProductSerializer change
  ships.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

app/components/explore/MainSection.tsx

@@ -104,6 +104,9 @@ const MainSection = () => {
               basePrice: product.basePrice
                 ? parseInt(product.basePrice)
                 : undefined,
+              sellerName: product.sellerName,
+              sellerLogo: product.sellerLogo,
+              sellerUsername: product.sellerUsername,
             };
           })}
           fetchNextPage={fetchNextPage}

app/routes/search.$query.tsx

@@ -66,6 +66,11 @@ export default function Search() {
                 id: product.id,
                 title: product.title,
                 images: product.imageUrls || [],
+                discountPercent: product.discountPercent || 0,
+                discountPrice:
+                  product.discountPrice || product.price || 0,
+                basePrice: product.basePrice || product.price || 0,
+                sellerName: product.sellerName,
               };
             }) || []
         }

src/api/types/models/index.ts

@@ -3309,6 +3309,24 @@ export interface Product {
      * @memberof Product
      */
     category?: string | null;
+    /**
+     *
+     * @type {string}
+     * @memberof Product
+     */
+    readonly sellerName?: string;
+    /**
+     *
+     * @type {string}
+     * @memberof Product
+     */
+    readonly sellerUsername?: string;
+    /**
+     *
+     * @type {string}
+     * @memberof Product
+     */
+    readonly sellerLogo?: string | null;
     /**
      *
      * @type {boolean}