- ReplayAsync fails when its restarted pump's stream has already ended, so
the supervisor backs off and stays Degraded instead of going Healthy over
a dead stream (whose next advise re-report restarted at attempt 1 with no
backoff - a tight reconnect loop).
- ReconnectSupervisor.AttemptInProgress (reopen through replay); advises
wait for a stale pump's replacement only while an attempt is running, not
for a whole backoff (the state still reads Reopening/Replaying there).
- ReconnectSupervisor: _disposed is set under the state lock and re-checked
inside ReportTransportFailure, so a late report cannot start a recovery
loop that StopAsync already missed.
- EventPump.HasEnded is a flag set before StreamRequested is released, and
a stream that ends/faults on its first MoveNext is marked ended first.
- SubscriptionRegistry fast path: a miss now falls through to the locked
path (lookup + session + window check atomically) instead of a lock-free
re-lookup.
- Tests: replay over an immediately-ending stream fails; AttemptInProgress
across attempt/backoff; ReportTransportFailure after stop; the
reopen-window test uses a generous wait bound.
Claude-Session: https://claude.ai/code/session_01GT67AD99zQQqpLCVm3p7xk
Joseph Doherty
8653960ea3