fix: add postgresql and redis statusInformers for Tier 2 instance health reporting

KOTS instance reporting was only tracking the gameshelf deployment.
Adding PostgreSQL and Redis StatefulSets so all major components
appear healthy in Vendor Portal instance details (rubric 2.10).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: aa-replicated

kots-app.yaml

@@ -6,3 +6,5 @@ spec:
   title: GameShelf
   statusInformers:
     - deployment/gameshelf
+    - statefulset/gameshelf-postgresql
+    - statefulset/gameshelf-redis-master