[Feature] IPv6 Dualstack Support in NAP/Karpenter

Overview:
Ability for existing and new clusters usingdualstack IPv6/IPv4 to be able to enable Node Auto Provisioning (NAP). Currently this experience is not available.

Status: In Progress

ETA: September 2026

Lack of support for IPv6 clusters per the placeholder code in [Azure Karpenter Provider](https://github.com/Azure/karpenter-provider-azure):

[karpenter-provider-azure/pkg/providers/loadbalancer/loadbalancer.go](https://github.com/Azure/karpenter-provider-azure/blob/2829d45ac24d10963802c201c720188ba6261594/pkg/providers/loadbalancer/loadbalancer.go#L105)

Line 105 in [2829d45](https://github.com/Azure/karpenter-provider-azure/commit/2829d45ac24d10963802c201c720188ba6261594)

// TODO: IPv6 deferred for now. When they're used they must be put onto a non-primary NIC.