AllNamespaces returns true if the list of namespaces watched is empty or contains only a blank string This implies that all namespaces are to be watched.

GetPodNamespace returns the value of the env var `POD_NAMESPACE` and defaults to `gloo-system` if unset.

NewKubeNamespaceClient creates and returns the `namespace.NewNamespaceClient` if it has permissions to list namespaces This entails creating a kubeclient, kubecorecache and calling a SelfSubjectAccessReview to verify if it has the appropriate RBAC.

ProcessWatchNamespaces appends the writeNamespace to the list of watchNamespaces passed if not already present and returns it.

NoOpKubeNamespaceWatcher to eliminate the need for this fake client for non kube environments Currently the generated code (event loop, snapshots) expects the KubeNamespaceClient to not be nil and the KubeNamespaceClient does not have checks to ensure it is handled properly if nil so this is the workaround for now until we rewrite the generated code.