Implement the Queue Change Job Entry endpoint for both the old NCP 17/6d
and newer NCP 17/7b variants.
Parse the queue job structure, look up the selected job by its job number,
and update the mutable job metadata fields while preserving server-managed
state such as client identity, entry time, job number, queue position, file
name/handle and servicing information.
Allow the job creator to update the standard user-changeable fields and allow
SUPERVISOR or Q_OPERATORS members to update the operator hold flag as well.
Return the documented queue/job/right/servicing completion codes for missing
queues, missing jobs, insufficient rights and jobs already being serviced.
This only updates NetWare queue metadata. It does not change the existing
Q_UNIX_PRINT/lp backend behavior and adds no CUPS dependency.
