One verify job per range: a plan container lists the mutants (diff taken at the
workspace root), stage 1 runs each file's mutants against that file's tests only
and decides only caught and unviable, stage 2 confirms every survivor, timeout,
unfiltered or zero-test file on the full suite, sharded over free slot leases,
and the merge prints one MUTANTS line and the final MISSED/TIMEOUT names.
NAMES reruns chosen survivors; TEST_ARGS skips flaky tests.
Deletes ygg-verify.sh's MISSED/TIMEOUT summary grep and its inline cargo mutants
usage example; the host-mode export gains YGG_SLOTS and YGG_ROOT. Briefs and
SKILL.md name the script; the mock docker grows /cm and /out, with a fake cargo
and a fake flock for the new test-tools.sh cases.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>