Asserting an absolute runtime.NumGoroutine() fails roughly one run in
three under -tags e2e, where the harness keeps a live server, its prober
and testcontainers goroutines alive alongside these tests.
- Match goroutine stacks naming the flight group, fan-out or prober
- Derive those frame names from method expressions
- Compare against a baseline sampled the same way
- Poll the prober's settle check instead of sampling it once
unkin-agent