Add new resource for Kubernetes API proxy (#279)

This adds a new resource which deploys a Kubernetes API server proxy
that can be used to access the API server without tokens through
Netbird.

Part of #274 

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## Summary by CodeRabbit

* **New Features**
* Added ClusterProxy custom resource for cluster API proxying
capabilities

* **Documentation**
  * Added ClusterProxy API reference documentation with schema details

* **Examples**
* Added example ClusterProxy configuration and RBAC setup for cluster
proxy targets

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pkg/applyconfigurations/utils.go

@@ -18,6 +18,12 @@ import (
 func ForKind(kind schema.GroupVersionKind) interface{} {
 	switch kind {
 	// Group=netbird.io, Version=v1alpha1
+	case v1alpha1.SchemeGroupVersion.WithKind("ClusterProxy"):
+		return &apiv1alpha1.ClusterProxyApplyConfiguration{}
+	case v1alpha1.SchemeGroupVersion.WithKind("ClusterProxySpec"):
+		return &apiv1alpha1.ClusterProxySpecApplyConfiguration{}
+	case v1alpha1.SchemeGroupVersion.WithKind("ClusterProxyStatus"):
+		return &apiv1alpha1.ClusterProxyStatusApplyConfiguration{}
 	case v1alpha1.SchemeGroupVersion.WithKind("ContainerOverride"):
 		return &apiv1alpha1.ContainerOverrideApplyConfiguration{}
 	case v1alpha1.SchemeGroupVersion.WithKind("CrossNamespaceReference"):