0119 — A stop request is not polled for a step that produced no data

ID	0119
Class	BUG
Severity	1
Status	ready

Models: —

Found: 2026-10-25 r2 review (PLAN.md Q2), fhsim 25024ce7

Evidence

src/engine/io/SimulationManager.cpp:184-188: WantsStop is only polled in PublishStep_, which runs only after a step that produced data. Since FHSIM R3-08 a NetworkStateProvider returns success with no data during a silent period.

Effect

An observer (for example the window of FhVis) cannot stop a run that is waiting for a silent publisher; only dataTimeout ends it.

Possible fix

Poll WantsStop in RunOneStep for every step, not only after data.

Test that would prove it

A fake provider that returns success with no data and an observer that asks to stop; Run() must return.

Risk

Low to medium: it changes when observers can stop a run.