A brief CDS network blip on 2026-04-15 returned HTTP 5xx from check_status
for multiple concurrently-polling workers. The old `{:error, _}` branches
consumed attempts, max_attempts=10 burned out in seconds, and 13 rows
were discarded with no cleanup — orphaned with no active poll worker,
including two rows that had both CDS legs done and were ready to decode.
Result: zero era5_profiles ever inserted despite 59 tile-months in flight.
Transient HTTP errors are now a `{:snooze, 60}` so a CDS outage pauses
polling instead of killing it. Terminal states (:failed, :rejected,
:not_found, :stuck) still drive the fail/resubmit paths.
Graham McIntire
662d7232e5