Scale GKE Vault to 1 replica while raft standby deadlock is unresolved

Pods 1 and 2 can't unseal because port 8201 (cluster port) only opens
after barrier initialization, but the barrier key transfer requires 8201
to be reachable — deadlock. Running single-node on pod 0 so
vault.neuralplatform.ai reliably routes to the active, unsealed instance.

servers/gcp/k8s/argocd-apps/vault-helm-gke.yaml

@@ -44,10 +44,13 @@ spec:
               add:
                 - IPC_LOCK
 
-          # HA mode — 3 replicas with Raft storage
+          # Single replica for now — raft standby unsealing requires the barrier
+          # key to be shared over port 8201 (cluster port), but 8201 only opens
+          # after unsealing (deadlock). Running solo on pod 0 until we resolve
+          # the standby bootstrap path. Scale back to 3 once fixed.
           ha:
             enabled: true
-            replicas: 3
+            replicas: 1
             raft:
               enabled: true
               setNodeId: true