Returns a hyperlink for a gem added to a socket. If the given socket contains a new gem (one that has been placed in the UI, but not yet confirmed for permanently socketing into the item), returns an item link for that gem. If the socket is empty or has a permanently socketed gem but no new gem, returns nil.

Only returns valid information when the Item Socketing UI is open (i.e. between the SOCKET_INFO_UPDATE and SOCKET_INFO_CLOSE events).