Support collection page wishlist icon for shops using metafield-linked separate products (non-variant grouping)

On shops where "variant-like" product groupings on collection pages are implemented via separate products linked by metafields (rather than true Shopify product variants), the wishlist/back-in-stock icon fails to render on the collection page for affected items. The current collection page logic assumes grouped items are variants of a single product, so it doesn't detect or render the icon for standalone products connected this way. Requesting support for detecting/rendering the icon on collection pages for products grouped via metafields, not just native Shopify variants.