When a systemic failure (provider outage, auth expiry, OOM) crashes
multiple workers simultaneously, detect_crashed_workers increments
each task failure counter independently. The circuit breaker only
trips after N × failure_limit retries across the fleet.
Fingerprint crash errors by normalizing host-specific details (PIDs,
timestamps). When 3+ tasks crash with the same fingerprint in a
single detection cycle, immediately trip the circuit breaker
(failure_limit=1) instead of waiting for repeated failures.
Isolated crashes (unique fingerprints) retain their normal retry
budget. Protocol violations continue to trip immediately.
Includes regression tests for systemic and isolated crash paths.
bradhallett
de9bcfc6a0