Dynamic PVC provisioning needed on new GCP instance.
Redis image 7.4.3-debian-12-r0 was removed from Docker Hub;
use floating 7.4-debian-12 tag instead.
PVC manifests: add volumeName to bind new PVCs to existing PVs whose
old PVCs were accidentally deleted during Terraform->ArgoCD migration.
All PVs patched to Retain to prevent data loss on pod restart.
kube-prometheus-stack: replace invalid adminPassword.valueFrom.secretKeyRef
(Helm values don't support k8s secretKeyRef syntax) with correct
admin.existingSecret + admin.passwordKey pattern.