Task 4.3: trace on all|job SEL... [level] [lines N] [file PATH], off and
status, parsed from the raw line; invalid arguments are named and leave
the settings unchanged; refcounted next/current settings; status shows
the settings in effect or pending, whole arrays as <base>[*], and stored
trace memory against its bound.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
