CheapShark redirect URL — use this for deal links when present (terms requirement)
enrichment — null until metadata lands (show a skeleton, not broken UI)
claim deadline for free-to-keep items; price-revert for discounts
end of a Steam play-for-free window — independent of endsAt
canonical store/claim URL — what the user should click
One catalog item — the single shape every catalog endpoint + WS event speaks.