return await context.Products.Select(p => new ProductListModel
{
    Id = p.Id,
    Name = p.Name,
    Price = p.Price,
    Description = p.Description,
    PictureUrl = p.PictureUrl,
    Categories =  p.ProductCategories.Select(pc => new CategoryListModel
                {
                    Id = pc.Category.Id,
                    Name = pc.Category.Name
                })
}).ToListAsnyc();