fix(supabase): enable request-termination plugin so Kong parses /healthz

Kong pod crashlooped on startup with:
  init_by_lua error: plugin 'request-termination' not enabled;
  add it to the 'plugins' configuration property

The chart sets KONG_PLUGINS as an explicit allowlist, and the
/healthz route we added in commit e61e6a8 uses the request-termination
plugin (bundled with Kong 2.8 but not enabled unless listed). Append
it. No image change, no new dependency -- just the plugin's name in
the comma-separated list.

This should be the last blocker: all the infrastructure for a healthy
supabase-kong backend is already in place (BackendConfig, checksum
annotation on the pod template, merged ingress with both hosts +
both ManagedCerts, the .invalid URL fix). With Kong able to parse its
declarative config, the pod can enter Ready, GCE's /healthz probe
returns 200, and api.0.knoe.dev / db.0.knoe.dev both start serving.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

supabase/helm/knoe-supabase/values.yaml

@@ -580,7 +580,12 @@ environment:
     KONG_DECLARATIVE_CONFIG: /usr/local/kong/kong.yml
     ## https://github.com/supabase/cli/issues/14
     KONG_DNS_ORDER: LAST,A,CNAME
-    KONG_PLUGINS: request-transformer,cors,key-auth,acl,basic-auth
+    # `request-termination` added for the /healthz route defined in
+    # templates/kong/config.yaml — Kong treats KONG_PLUGINS as an allowlist
+    # (only listed plugins can be referenced in the declarative config), so
+    # without this entry the Kong pod crashlooped with
+    #   init_by_lua error: plugin 'request-termination' not enabled
+    KONG_PLUGINS: request-transformer,cors,key-auth,acl,basic-auth,request-termination
     KONG_NGINX_PROXY_PROXY_BUFFER_SIZE: 160k
     KONG_NGINX_PROXY_PROXY_BUFFERS: 64 160k
     KONG_LOG_LEVEL: warn