For a Hypergrid user, delay estate access checks until NewUserConnection() so that they work.

This is necessary because the hypergrid groups checks (as referenced by estates) require an agent circuit to be present to construct the hypergrid ID.
However, this is not around until Scene.NewUserConnection(), as called by CreateAgent() in EntityTransferModule.
Therefore, if we're dealing with a hypergrid user, delay the check until NewUserConnection()/CreateAgent()
The entity transfer impact should be minimal since CreateAgent() is the next significant call after NewUserConnection()
However, to preserve the accuracy of query access we will only relax the check for HG users.

OpenSim/Region/Framework/Scenes/Scene.cs

@@ -5739,7 +5739,11 @@ namespace OpenSim.Region.Framework.Scenes
 
             try
             {
-                if (!AuthorizeUser(aCircuit, false, out reason))
+                // If this is a hypergrid user, then we can't perform a successful groups access check here since this
+                // currently relies on a circuit being present in the AuthenticateHandler to construct a Hypergrid ID.
+                // This is only present in NewUserConnection() which entity transfer calls very soon after QueryAccess().
+                // Therefore, we'll defer to the check in NewUserConnection() instead.
+                if (!AuthorizeUser(aCircuit, !UserManagementModule.IsLocalGridUser(agentID), out reason))
                 {
                     //m_log.DebugFormat("[SCENE]: Denying access for {0}", agentID);
                     return false;