Create an inventory item

Creates a single inventory item in the studio the API key is issued for, and returns it once it exists. No Idempotency-Key header is required. If the request times out (504) or fails upstream (502) the item may still have been created, so the response returns an Idempotency-Key header: retrying with that value returns the item the first attempt created rather than creating a second. You may optionally send your own Idempotency-Key on the first request and that will be used.