CI (portable, run #38) intermittently failed SessionManagerTests
.InvokeAsync_WhenTimeoutZero_FailsFastUnchanged with 'expected immediate
fail-fast but took 155ms'. The fail-fast paths throw synchronously under the
lock (GatewaySession.GetReadyWorkerClientAsync) and never enter the poll loop,
so the absolute <100ms wall-clock bound measured only host load, not behavior,
and flaked under CI contention.
- WhenWorkerFaulted_FailsFastWithBothStates: anchor the bound to a large (5000ms)
ready-wait timeout and assert fail-fast returns in < timeout/3 — a regression
that burned the timeout is still caught, but scheduling jitter can't trip it.
- WhenTimeoutZero_FailsFastUnchanged: drop the wall-clock assertion entirely
(a zero timeout has no wait window to burn); the error code, both-states
message, and InvokeCount == 0 already pin the immediate fail-fast.
Verified: the 3 SessionManager timing tests pass (net10.0).
Joseph Doherty
df7e20db1d