The CAA branch of _upgrade_art_url capped art at the /front-1200 thumbnail —
a deliberate flakiness trade-off, but the policy had rotted into inconsistency:
iTunes art already shipped at 3000x3000, and bare /front URLs (release-group
lookups — exactly what the Re-tag flow produces) bypassed the cap entirely,
which is how Sokhi observed retag delivering full-res while downloads got 1200.
CAA URLs now upgrade to the bare /front ORIGINAL (native res, frequently
3000px+). The flakiness concern that motivated the old cap is handled where it
belongs, in the fetch: _fetch_art_bytes now walks an attempt chain — original
-> /front-1200 midpoint -> the original sized thumbnail — so a flaky
archive.org degrades to the old 1200px behavior, never below it.
Tests updated to the new contract (+3 chain tests: native-first, flaky
degrades to 1200 not 250, full chain ends at the thumbnail). 623 metadata +
1267 art-path tests pass.
c6d1dede2b