FEAT(observability): enable HA with replica 2 and soft anti-affinity

- Add replicaCount: 2 to goldilocks, vpa, alertmanager
- Add replicas: 2 to loki singleBinary
- Add soft pod anti-affinity for node distribution
- Keep kube-state-metrics at replica 1 to prevent duplicate metrics

FIX(loki): revert to replica 1 for Single Binary mode

- Single Binary mode cannot run more than 1 replica without object storage
- Remove affinity configuration for single replica
- Keep filesystem storage backend

loki/helm-values.yaml

@@ -37,6 +37,7 @@ deploymentMode: SingleBinary
 
 singleBinary:
   replicas: 1
+  # Note: Single Binary mode cannot run more than 1 replica without object storage backend
   persistence:
     enabled: true
     size: 5Gi  # Reduced from 10Gi to save storage
@@ -47,6 +48,7 @@ singleBinary:
       memory: 462Mi
     limits:
       memory: 462Mi
+  # Note: Affinity not needed for single replica
 
 # Disable components not needed in single binary mode
 backend: