Add optional URL to Product type and update Link component

Updated the `Product` type in `product-service.ts` to include an optional `url` property. Modified the `Link` component in `product-item.tsx` to use this new `url` for navigation, defaulting to '/404' if not provided. This enhances product item display by making product names clickable.

src/client/dd-hub-react/src/api/product-service.ts

@@ -7,6 +7,7 @@ export type Product = {
     coverUrl?: string;
     colors?: string[];
     priceSale?: number;
+    url?: string;
 };
 
 /**

src/client/dd-hub-react/src/sections/product/product-item.tsx

@@ -93,7 +93,7 @@ export function ProductItem({ product }: { product: Product }) {
       </Box>
 
       <Stack spacing={2} sx={{ p: 3 }}>
-        <Link color="inherit" underline="hover" variant="subtitle2" noWrap>
+        <Link color="inherit" underline="hover" variant="subtitle2" noWrap target="_blank" href={product.url ?? '/404'}>
           {product.name}
         </Link>