Add to Cart via SKU

[hahnzilla]

What are you trying to do?
We'd love to have a core way of adding an item to the cart by the sku rather than the purchasable id.

Was thinking this could be a useful feature so you don’t have to track
around the combo of SKU/purchasableId. We have a few places where we hard
code the SKU throughout the repo for “reasons” but we feel much better
doing this because that SKU is unlikely to change (especially across
environments). We try to use the core commerce add to cart because
we’ve had issues rolling our own in the past.

What's your proposed solution?
Our call to the endpoint currently looks like

      return $axios.post('/actions/commerce/cart/update-cart', {
            qty: item.qty,
            id: item.id
      })

and would love the option of using the SKU

      return $axios.post('/actions/commerce/cart/update-cart', {
            qty: item.qty,
            sku: item.sku
      })

[lukeholder]

Thanks @dhahn - leaving is open as a good feature request, but not looking to add this in the short-term.