Historical pricing evidence is now reloaded only when its card, source, language, variant, grader and grade match the requested market identity. Legacy rows with unknown identity fields are deliberately excluded instead of being attributed to an exact raw or slab estimate.

Issue: https://github.com/snag-tcg/tcg-collector-backend/issues/290

Implementation merged into backend staging: https://github.com/snag-tcg/tcg-collector-backend/pull/292

This is evidence isolation, not an M1 or M2 valuation-formula change. It performs no migration or backfill, so unattributable legacy rows reduce coverage rather than contaminating an estimate, and it does not publish slab estimates. A merge into staging is not proof of production deployment or pricing publication. GitHub-hosted checks did not start because of the account billing/spending limit; the PR records passing local unit and typecheck suites, while the database-backed E2E environment was unavailable.