True after the participant has entered the route, e.g., player pressed join on a shared action.
This boolean flag (bool) belongs to FInteractionRuntimeParticipantSnapshot under InteractionRuntime.
Blueprint or editor workflows can write this value when constructing, overriding, or customizing the owning object.
UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "InteractionRuntime")
bool bEntered = false;