Add product to wishlist

curl --request POST \
  --url https://services.commercengine.dev/api/v1/x2yh61zw4k/storefront/wishlist/{user_id} \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '{
  "product_id": "01F3Z7KG06J4ACWH1C4926KJEC",
  "sku": "<string>"
}'

{
  "message": "<string>",
  "success": true
}