* ci: add macOS test job
Darwin-tagged tests (Seatbelt translator, diagnostics, upcoming network
lockdown tests) never ran in CI: the test matrix covered ubuntu and
windows only. The M0 sandbox lockdown milestone is macOS-first, so macOS
coverage must exist before enforcement work lands.
Also establishes the convention that darwin integration tests requiring
sandbox-exec must fail (not skip) when running in CI, so missing tooling
cannot silently hide security tests.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PqMU5GNBbQvQct9nxek1VS
* test(sandbox): make Seatbelt render golden test machine-independent
The golden file baked the authoring machine's HOME, CWD and TMPDIR parent
into the expected profile, so TestRenderSeatbelt_Golden could only pass on
that machine. It never ran in CI before the macOS job exposed it.
Normalize CWD, home and TMPDIR parents (raw and query-escaped forms) to
stable placeholders before comparison, longest path first so prefix
overlaps survive, and rewrite the golden accordingly.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PqMU5GNBbQvQct9nxek1VS
* ci: make setup-go cache explicit in macOS job
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PqMU5GNBbQvQct9nxek1VS
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Co-authored-by: Claude <noreply@anthropic.com>
