Include Karpenter-provisioned nodes into consideration

[logyball]

Addresses #3 : Karpenter Support

Karpenter does not provision nodes as part of a node group/pool. However, they are still useful to see when listing groups or pools of nodes. This development allows for nodes that have been provisioned by karpenter to be identified by the plugin.

# list
❯ kubectl nodepools list
NAME                    NODES   TYPE
(Karpenter) default         2   c6a.2xlarge
main-m52xl-2                4   m5.2xlarge

# label search
❯ kubectl nodepools nodes --label 'karpenter.sh/provisioner-name' default
NODE                                            STATUS
ip-10-62-71-26.us-east-2.compute.internal       Ready
ip-10-62-79-122.us-east-2.compute.internal      Ready

Note that multiple instance types can be present for a single karpenter provisioner, so output can look like this:

# list
❯ kubectl nodepools list
NAME                    NODES   TYPE
(Karpenter) default         2   c6a.2xlarge, m5.2xlarge
main-m52xl-2                4   m5.2xlarge

This has been achieved by restructuring how the nodepool struct is implemented, by having "Types" be a set rather than a single value.

[inkel]

I like it! Can you address my suggestion, though? I'm ok to debate it! 😸

[FalconerTC]

Works great! Thank you!