Merge branch 'development' of https://github.com/o3de/o3de into Network/olexl/hierarchy_optimizations_cr

Gems/Multiplayer/Code/Include/Multiplayer/IMultiplayer.h

@@ -48,6 +48,7 @@ namespace Multiplayer
     using NotifyClientMigrationEvent = AZ::Event<const HostId&, uint64_t, ClientInputId>;
     using NotifyEntityMigrationEvent = AZ::Event<const ConstNetworkEntityHandle&, const HostId&>;
     using ConnectionAcquiredEvent = AZ::Event<MultiplayerAgentDatum>;
+    using ServerAcceptanceReceivedEvent = AZ::Event<>;
     using SessionInitEvent = AZ::Event<AzNetworking::INetworkInterface*>;
     using SessionShutdownEvent = AZ::Event<AzNetworking::INetworkInterface*>;
 
@@ -122,6 +123,10 @@ namespace Multiplayer
         //! @param handler The ConnectionAcquiredEvent Handler to add
         virtual void AddConnectionAcquiredHandler(ConnectionAcquiredEvent::Handler& handler) = 0;
 
+        //! Adds a ServerAcceptanceReceived Handler which is invoked when the client receives the accept packet from the server.
+        //! @param handler The ServerAcceptanceReceived Handler to add
+        virtual void AddServerAcceptanceReceivedHandler(ServerAcceptanceReceivedEvent::Handler& handler) = 0;
+
         //! Adds a SessionInitEvent Handler which is invoked when a new network session starts.
         //! @param handler The SessionInitEvent Handler to add
         virtual void AddSessionInitHandler(SessionInitEvent::Handler& handler) = 0;