Many pages don't show up in the navigation

[nfnt]

Which page is affected?: Many, among them the examples, e.g. for Apache Kafka, the whole testing folder, the contributing page

What exactly is broken?: These pages aren't shown in the left-side menu but are part of the documentation repo. Some of these pages are actually rendered and reachable under their intended URL, e.g. https://kudo.dev/docs/contributing.html.

[nfnt]

Kind of related, see also kudobuilder/kudo#142: The examples don't use kubectl kudo but still rely on kubectl apply -f.