stable version in place and gradually migrate apps to the new version.

- More flexibility: the new installer allows multiple 'environments', allowing applications to select
a set of control plane settings and components. While the entire mesh respects the same APIs and config,
apps may target different 'environments' which contain different instances and variants of Istio.

        exec:
          command:
          - pilot-agent
          - wait
  {{- else if $nativeSidecar }}
    {{- /* preStop is called when the pod starts shutdown. Initialize drain. We will get SIGTERM once applications are torn down. */}}
    lifecycle:
      preStop:
        exec:
          command:
          - pilot-agent
          - request

        exec:
          command:
          - pilot-agent
          - wait
  {{- else if $nativeSidecar }}
    {{- /* preStop is called when the pod starts shutdown. Initialize drain. We will get SIGTERM once applications are torn down. */}}
    lifecycle:
      preStop:
        exec:
          command:
          - pilot-agent
          - request

|PROV_CERT|certificates to be used for mTLS communication with control plane only; NOT for workload mTLS|
|OUTPUT_CERT|write all fetched certificates to some directory. Used to support applications that need certificates (Prometheus) as well as rotating mTLS control plane authentication.|
|FILE_MOUNTED_CERTS|completely disable CA path, exclusively use certs mounted into the pod with set certificate file locations|

Fundamentally, this component is responsible for the following:

- Sets up redirection with newly-started (or newly-added, previously-started) application pods such that traffic from application pods is forwarded to the local node's ztunnel pod.
- Configures required iptables, sockets, and packet routing miscellanea within the `ztunnel` and application pod network namespaces to make that happen.

This component accomplishes that in the following ways:

	if err != nil {
		return nil, fmt.Errorf("failed to get system cert pool: %w", err)
	}
	gcpCreds, err := oauth.NewApplicationDefault(ctx)
	if err != nil {
		return nil, fmt.Errorf("failed to get application default credentials: %w", err)
	}

	return []grpc.DialOption{
		grpc.WithTransportCredentials(credentials.NewTLS(&tls.Config{
			RootCAs:    systemRoots,
			MinVersion: tls.VersionTLS12,
		})),

    # see
    # https://kubernetes.io/docs/concepts/services-networking/dns-pod-service/#dns-config
    # This does not apply to gateway pods as they typically need a different
    # set of DNS settings than the normal application pods (e.g., in
    # multicluster scenarios).
    # NOTE: If using templates, follow the pattern in the commented example below.
    #podDNSSearchNamespaces:
    #- global

                          "on_match": {
                            "matcher": {
                              "matcher_tree": {
                                "input": {
                                  "name": "application-protocol",
                                  "typed_config": {
                                    "@type": "type.googleapis.com/envoy.extensions.matching.common_inputs.network.v3.ApplicationProtocolInput"

                          "on_match": {
                            "matcher": {
                              "matcher_tree": {
                                "input": {
                                  "name": "application-protocol",
                                  "typed_config": {
                                    "@type": "type.googleapis.com/envoy.extensions.matching.common_inputs.network.v3.ApplicationProtocolInput"

                          type: object
                        tunnel:
                          description: Configuration of tunneling TCP over other transport
                            or application layers for the host configured in the DestinationRule.
                          properties:
                            protocol:
                              description: Specifies which protocol to use for tunneling