feat: add read-only proxy

[jcpunk]

A number of folks (myself included) are fond of the skip-login button from the previous versions.

I'm glad for the move to the new, better auth. However, a number of my users have asked after the simple read-only view they once had.

This PR adds a fairly naive proxy container which sets the Authorization header to a specially created read-only user.

There are probably more things to template, maybe network policies to enforce, and tls to attach. But for a quick and simple "Give me a read-only view" this works for my site.

[k8s-ci-robot]

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This pull-request has been approved by: jcpunk
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