User hosted by another cluster node that is presente in a local room. Remote users are
only created when processing unavailable presences sent when the node hosting the actual
user went down. Each cluster node remaining in the cluster will create an unavailable
presence for each user hosted in the cluster node that went down as a way to indicate
the remaining room occupants that the user is offline.
Obtain the address of the user. The address is used by services like the core
server packet router to determine if a packet should be sent to the handler.
Handlers that are working on behalf of the server should use the generic server
hostname address (e.g. server.com).