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/api/v1alpha1/clusterproxystatus.go

@@ -0,0 +1,47 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+// Code generated by controller-gen. DO NOT EDIT.
+
+package v1alpha1
+
+import (
+	v1 "k8s.io/client-go/applyconfigurations/meta/v1"
+)
+
+// ClusterProxyStatusApplyConfiguration represents a declarative configuration of the ClusterProxyStatus type for use
+// with apply.
+//
+// ClusterProxyStatus defines the observed state of ClusterProxy.
+type ClusterProxyStatusApplyConfiguration struct {
+	// ObservedGeneration is the last reconciled generation.
+	ObservedGeneration *int64 `json:"observedGeneration,omitempty"`
+	// Conditions holds the conditions for the ClusterProxy.
+	Conditions []v1.ConditionApplyConfiguration `json:"conditions,omitempty"`
+}
+
+// ClusterProxyStatusApplyConfiguration constructs a declarative configuration of the ClusterProxyStatus type for use with
+// apply.
+func ClusterProxyStatus() *ClusterProxyStatusApplyConfiguration {
+	return &ClusterProxyStatusApplyConfiguration{}
+}
+
+// WithObservedGeneration sets the ObservedGeneration field in the declarative configuration to the given value
+// and returns the receiver, so that objects can be built by chaining "With" function invocations.
+// If called multiple times, the ObservedGeneration field is set to the value of the last call.
+func (b *ClusterProxyStatusApplyConfiguration) WithObservedGeneration(value int64) *ClusterProxyStatusApplyConfiguration {
+	b.ObservedGeneration = &value
+	return b
+}
+
+// WithConditions adds the given value to the Conditions field in the declarative configuration
+// and returns the receiver, so that objects can be build by chaining "With" function invocations.
+// If called multiple times, values provided by each call will be appended to the Conditions field.
+func (b *ClusterProxyStatusApplyConfiguration) WithConditions(values ...*v1.ConditionApplyConfiguration) *ClusterProxyStatusApplyConfiguration {
+	for i := range values {
+		if values[i] == nil {
+			panic("nil value passed to WithConditions")
+		}
+		b.Conditions = append(b.Conditions, *values[i])
+	}
+	return b
+}