Current number of participants in the route, e.g., "2 players joined".
This numeric value (int32) belongs to FInteractionRuntimeMultiParticipantParticipantEvent under InteractionRuntime|MultiParticipant.
Blueprint or editor workflows can write this value when constructing, overriding, or customizing the owning object.
UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "InteractionRuntime|MultiParticipant")
int32 CurrentParticipants = 0;