The 18 active rows keep compile + cs==ws byte-id and the tab-anchored
ADDQ $N,SP cleanup markers with both polarities (mem-class rows must
contain their slot's cleanup; the exactly-48B boundary row must not).
The per-row driver build+run legs (incl. the uninit-global zero-box
exit 91) move to the r929 run fixture corpus per the residual audit
port split; the four buildfail rows were already dead here, owned by
the r929_memarg_reject_* fixtures.