Core entities

5.2 Core entities

The cardinalities matter: one receipt has many line items, one line item resolves to at most one canonical product (or none if it falls in the pending queue), one receipt emits at most one trust score (it can be re-scored, but each version supersedes the last). Reward accounting flows through append-only contribution_point_events rows and per-epoch snapshot leaves (5.7); the price ledger receives identity-free observation rows (5.6).