fix: normalize CSI empty-zone topology value to regional zone "0"

[andyzhangx]

Register a NormalizedLabelValues mapping so that when the Azure Disk CSI topology key (topology.disk.csi.azure.com/zone) is normalized to the well-known topology key (topology.kubernetes.io/zone), the empty string value ("") used by the CSI driver for non-zonal disks is translated to "0" (the fault domain value cloud-provider-azure assigns to regional VMs).

Problem

When the Azure Disk CSI driver creates a PV for a non-zonal (regional) disk, it sets:

nodeAffinity:
  required:
    nodeSelectorTerms:
    - matchExpressions:
      - key: topology.disk.csi.azure.com/zone
        operator: In
        values:
        - ""

Karpenter normalizes this key to topology.kubernetes.io/zone but preserves the value "". However, regional nodes in Karpenter offerings use zone value "0" (from cloud-provider-azure). This mismatch causes "" ∉ {"0"} → no offering matches → pods with non-zonal PVCs remain permanently pending.

Fix

Add value normalization in init() using the new NormalizedLabelValues API:

karpv1.NormalizedLabelValues[corev1.LabelTopologyZone] = map[string]string{"": zones.Regional}

Dependencies

• feat: add NormalizedLabelValues for value translation during label normalization kubernetes-sigs/karpenter#3104 — adds NormalizedLabelValues support to karpenter-core