The replayed commit's cascade exits the current stage in its first
hop. false is a definite answer for the current state — including
a selection halted by an unevaluable trigger, which holds the stage.
OptionaltransitionThe transition the selection picked, present iff exitsStage.
The flow consequence of one caller fire, computed by replaying it in memory through the same machinery a real commit runs — never by a parallel model of it. State-dependent: it answers "now", not "always".