implement server and client player join/leave notifications

src/client/handlers/PlayerLeaveHandler.cpp

@@ -0,0 +1,29 @@
+#include <client/handlers/PlayerLeaveHandler.h>
+
+namespace blitz {
+namespace client {
+
+PlayerLeaveHandler::PlayerLeaveHandler(network::EnetConnection& a_Connection, EnttWorld& a_World) :
+	protocol::PacketHandler(a_Connection, a_World) {
+	m_Slot.Connect(m_Connection.OnPlayerLeave, this, &PlayerLeaveHandler::Handle);
+}
+
+void PlayerLeaveHandler::Handle(const protocol::data::PlayerLeave& a_PlayerLeave) {
+	auto world = m_World.load();
+
+	entt::entity playerLeft;
+
+	for (auto [player, playerInfo] : world->GetRegistry().view<PlayerInfoComponent>().each()) {
+		if (playerInfo.m_PlayerId == a_PlayerLeave.m_PlayerId) {
+			playerLeft = player;
+			break;
+		}
+	}
+
+	world->GetRegistry().destroy(playerLeft);
+}
+
+PlayerLeaveHandler::~PlayerLeaveHandler() {}
+
+}  // namespace client
+}  // namespace blitz