Validate deploy/infra manifests in CI (helm lint/template, docker-compose, workflow lint)

[LiorFink00]

Found during a full feature-coverage audit on main (fc58e08). These features work (verified live where reachable) — the gap is missing automated tests, not broken behavior.

Deploy/infra artifacts have no automated validation — a broken manifest ships silently:

• Helm chart (deploy/helm/thumper/) — add helm lint + helm template to CI. The tests/test-connection.yaml hook only runs under live helm test, never in CI.
• docker-compose.yml — add a docker compose config validation step.
• Workflow YAML (.github/workflows/*.yml, .github/actions/) — add actionlint; only the tripwire action's JS is tested today.
• Optionally: a container runtime smoke test (boot the built image, assert /healthz 200) — currently only the docker build is checked, though I verified the container boots + serves live.