feat(kuma-cp): implement possibility to select proxies in policies by new kind Dataplane

[Automaat]

Motivation

We want to be able to target proxies by new kind Dataplane. We want to select Dataplanes by name/namespace, by labels and select single inbound by its name

Supporting documentation

This is based on Inbound policies MADR

Fix #12359

[github-actions]

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• This will not break child repos: it doesn't hardcode values (.e.g "kumahq" as an image registry)
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[Automaat]

I've purposefully hardcoded this stuff as I wanted something simple, as it is used in single test, we can improve on this in the future if we need some more customizability

[lobkovilya]

name and namespace in targetRefs refer to the real name/namespace of the resource, you shouldn't check the displayName, you have to construct ResourceIdentifiers from DPP and from targetRef and see if they're equal (with ==). See how we handle to[].targetRef

kuma/pkg/plugins/policies/core/rules/outbound/resourcerules.go

Line 226 in 00cbfa3

func resolveTargetRef[T interface {

[lobkovilya]

I extracted the function that resolves targetRefs to rules_common package, I think it should be possible to use it for DPPs as it exactly the same approach (the change is not in master yet):

kuma/pkg/plugins/policies/core/rules/common/resolvetargetref.go

Line 33 in 5c48b20

func ResolveTargetRef(targetRef common_api.TargetRef, tMeta core_model.ResourceMeta, reader ResourceReader) []*ResourceSection {