RealMxGatewayClient.RunEventLoopAsync stored every streamed MxEvent's
WorkerSequence as its StreamEvents resume cursor before filtering by family.
The gateway's control sentinels (ReplayGap on a resume that hit evicted
events; the opt-in StreamAttached ack) carry worker_sequence 0, so a gap
reset the cursor to 0 and the next resume became a fresh stream: no replay,
no gap signal, silent loss.
Cursor rule: advance-only (max), from real worker events (sequence > 0) only.
A ReplayGap anchors the cursor at oldest_available_sequence - 1 (the gateway's
documented gap-free resume point, valid for an empty ring too) and is logged
as a warning naming the lost interval. Sentinels never reach the value
callback.
The loop body is split into internal RunEventLoopCoreAsync(IAsyncEnumerable)
so tests drive a scripted stream; 4 of the 7 new tests fail on the old loop.
Claude-Session: https://claude.ai/code/session_01GT67ACmpMR7b9LGRPLijMi
Joseph Doherty