Read-only admin view for maintainers

[fricklerhandwerk]

As a Nixpkgs maintainer, I want to inspect the security tracker data in case the UI fails me. Since downloading a complete database dump may take >30min but I typically would only look at a few entries, all I need is an easily accessible, faithful representation of the database contents.

Implementation notes:

• This may get painful because Django has opinions on what an "admin" is
• In order to scale with the proper frontend, it would require modeling permissions in the ORM rather than in views
• Yes, that's a second UI to maintain, but we already have done it since the beginning because it has proven quite valuable to be able to click around quickly