[BUG] docs `Container Setup Guide` not referenced

[kornerc]

Describe the bug

The documentation Container Setup Guide is not referenced in the docs (it is only findable by searching after it or having the link).

Expected behavior

The page Container Setup Guide is referenced in the table of contents.

PS you can assign me to this task and I can also adjust the documentation about the dev-containers a little bit

[nitbharambe]

@kornerc Maybe you already figure it out: It's entry is missing in docs/index.md.

[nitbharambe]

I see multi dimensional batch calculation is also not included in index.md. Lets add it to scope of this ticket.