close server when empty

src/game/server/Server.cpp

@@ -145,6 +145,10 @@ void Server::OnPlayerJoin(std::uint8_t id) {
 void Server::OnPlayerLeave(std::uint8_t id) {
 	protocol::PlayerLeavePacket packet(id);
 	BroadcastPacket(&packet);
+
+	if (GetPlayers().empty()) {
+		Close();
+	}
 }
 
 } // namespace server