Fix: is_saved always false in /api/v1/products response even with valid token

[ngarahmady]

Hi Bagisto team 👋

I'm using the /api/v1/products endpoint to fetch the list of products for an authenticated customer.

Each product in the response includes an is_saved field. However, even if the customer has already added that product to the wishlist, the value of is_saved is always false.

Example:

1. /api/v1/customer/wishlist confirms that product ID 2166 is in wishlist.
2. But /api/v1/products returns:

{ "id": 2166, "is_saved": false }

Expected:

If the customer is authenticated via Bearer token, and a product is already wishlisted, then is_saved should return true for that product in the /products response.

Why it matters:
Many frontend apps show a wishlist (heart icon) in product grids and search results. Without a reliable is_saved, they have to cross-match with /wishlist manually.

Thanks in advance for fixing this! 🙏