AWS Network Load Balancer integration with EKS Anywhere Cluster

**What would you like to be added**:

Network workflow:

AWS NLB -> nginx-ingress (running on EKS A Cluster) => application pods (running on EKS A Cluster)

**Why is this needed**:
curated packages do not support AWS Load Balancers at the moment.

- https://github.com/kubernetes-sigs/aws-load-balancer-controller

Start by reviewing how curated packages handle networking in EKS Anywhere and the linked aws-load-balancer-controller project. Confirm the supported AWS NLB-to-nginx-ingress-to-application-pods workflow and identify the package, configuration, and validation work needed for that integration.

Written by the indexing model from the issue text.