Stale xtrn (external program/door) configuration used in node status

Programs (e.g. umonitor, gtkmonitor) that use nodestatus() from userdat.c use the index into scfg.xtrn[] to get the external program being run. This index can change if external programs are added or removed from xtrn.ini (e.g. using SCFG).

Other scripts/logic in SBBS use the xtrn program code read from the user's record to determine the program being run. nodestatus() should be updated to the same for consistency/accuracy.

This issue was reported on DOVE-Net by kk4qbn (KK4QBN)