Inventory semantics - Nektir API

Inventory is an observation of what a public upstream response reported when Nektir retrieved it. It is not a transactionally current Utah DABS inventory ledger.

Observation states

State	Meaning
`reported_positive`	The reviewed source row reported a quantity greater than zero.
`reported_zero`	The reviewed source row explicitly reported zero.
`row_absent`	Retrieval succeeded for the product and store scope, but the expected store row was absent.
`unchecked`	No successful observation covers this product-store pair under the stated scope and policy.

row_absent and unchecked are not converted into zero.

Quantity scopes

Store quantity, warehouse quantity, and on-order quantity are separate fields. Never sum them to create a store-availability number. Warehouse or on-order stock does not establish availability at a consumer store.

Purchase eligibility

Reported stock and ordinary consumer purchase eligibility answer different questions. Check the product and store policy fields even when a positive quantity is present. Restricted, licensee-only, package-agency, discontinued, and unknown states must remain visible to application logic.