A Retry-After longer than the 10 s retry budget used to sleep the whole
budget out and then give up, so the proxy's 429 pause started 10 s late
and every new-point poll in that window still went upstream and logged.
The retry loop now stops at once in that case.
Tests: the retry loop no longer sleeps for an unreachable Retry-After;
fully cached points, including stale ones, are served during the pause
with no upstream call; a 503 does not pause; a shorter concurrent
Retry-After never cuts the pause short. CURRENT-STATE now says which
requests are still served and which log.
Use 64-point browser and upstream terrain batches to reduce cold-cache timeouts. Preserve successful chunk results, distinguish absent readings from malformed responses, and reject fabricated zero heights.
Original terrain resilience contribution by ItzDESTAQ, with browser batching, validation and regression follow-up by Sameh Khamis.
Validated with unit/build/format/boundary checks, 108 tracking checks, 5 terrain-outage checks, controlled slow-upstream comparison and live browser checks.
Co-authored-by: ItzDESTAQ <[email protected]>
Co-authored-by: Sameh Khamis <[email protected]>