Pass the correct position to QueryAccess() instead of UUID.Zero (it was wrong in one place)
When preparing a Hypergrid teleport, tell the receiving grid which user is entering the grid.

This can affect which region to use. E.g., returning users may be allowed to enter any region, whereas users from other grids will have to enter a gateway region. Previously per-user decisions were only made later, but by then it's too late to change which region the user enters.
Fixed: during a teleport we always sent the error "The teleport destination could not be found" to the client. This happened on both success and failure.

On successful teleports this error wasn't actually shown to the user. But on failed teleports this error could hide the true cause of the failure. For example, attempting to use a Landmark that's more than 4095 regions away would result in two warnings appearing in the viewer: "Region too far" and "Destination could not be found". The second message hid the first one, so it wasn't obvious to the user what is actually the problem.