Closes issue #37. The Bitnami postgresql subchart's auto-generated
NetworkPolicy restricted the port (5432) but not the source - any pod in
any namespace could reach it, since additive NetworkPolicy rules can't
restrict an existing permissive one, only the chart itself controls it
(hence not touched during the original #10 rollout).
Disabled via postgresql.primary.networkPolicy.enabled: false and replaced
with a scoped policy allowing only authentik-server and authentik-worker
(same namespace) on 5432, matching the pattern already used for the
matrix namespace's postgres access. No metrics exporter is enabled for
this instance, so no monitoring-namespace rule is needed.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>