ci-hygiene guard: lockfile-only installs, pinned images, no host-port services (warn-only)

House rule 6 (09-23). The bridge now also posts windy-git/ci-hygiene on
every PR head (added lines) and default branch (whole files), scanning CI
workflows and Dockerfiles for: floating pip / uv pip installs (not -r,
not --no-deps, not exact pins), uv sync without --locked/--frozen,
npm install instead of npm ci (unless every package is exact-pinned),
yarn/pnpm without a frozen lockfile, :latest images and COPY lock* globs
(Windy Mail #147), and CI services publishing a HOST port (every job
shares one dind: Windy Mind runs 147/176 died on 5432). Warn-only;
CI_HYGIENE_MODE=block later. Allow-list ci/ci-hygiene-allow.yml (empty).

compute_guard's walker is now parameterised (line_fn / path_ok /
prefilter) so both guards share one scanner, cache and allow loader; the
bridge posts both through one _post_guard. Today: 95 issues in 21 repos;
windy-git, calendar, traveler, traveler-site clean.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

ci/ci-hygiene-allow.yml

@@ -0,0 +1,5 @@
+# CI hygiene allow-list: installs that may float, or services that may publish
+# a host port. House rule 6 (09-23): installs come from a lockfile. Every entry
+# is an exception and MUST say why. Paths are fnmatch globs from the repo root.
+# Owner: Windy Git lane (13); changes go through the orchestrator.
+allow: []