Remove paths filters from contributor-check and supply-chain-audit
workflows. When no matching files changed, the workflows never ran and
the required checks (check-attribution, supply chain scan, dep bounds)
stayed "pending" forever, blocking merge.
Now both workflows always trigger. A path-check step/job determines
whether the real work should run; gate jobs with matching names report
success when the real job was skipped, so branch protection always
gets a check status.
Also fixes dep-bounds: the old condition
if: contains(github.event.pull_request.changed_files_url, 'pyproject.toml') || true
was always true (the || true made it unconditional). Now uses the
proper changes.deps output from the shared filter job.
6bc309baf2