Two CI reds from the previous commits.
benchmark_browser_eval.py moved from scripts/ (exempt) to evals/ and its
bare shutil.which("npx") tripped test_no_unreviewed_bare_managed_runtime_
lookups. evals/ are standalone user-invoked benchmark programs, the same
class as scripts/ and skills/, and three other eval files already call
which() the same way; the guard just never saw them because the harness
that carried them lived under scripts/. Exempt the directory.
list_os_marked_tests.py used Path.rglob, which raises FileNotFoundError
when a __pycache__ directory disappears mid-scan (a sibling job in the
same workspace). The managed-runtime guard already switched to os.walk
for the identical TOCTOU; do the same here. Same output, sorted.