Better question sequence

I've been thinking of using https://github.com/charmbracelet/bubbletea to revamp the `microcloud init` command sequence a bit

One possible idea is having submenus rather than a sequence of questions, like this:
https://github.com/charmbracelet/bubbletea/tree/master/examples#multiple-text-inputs

But instead of text inputs, we can put the storage & network questions behind these labelled submenus:
```
> Setup local storage
> Setup distributed storage
> Setup distributed network
> Print summary (as preseed?)
> Deploy MicroCloud
```

This would make the setup a bit clearer, and incompatibilities like incorrectly configured network interfaces can be noticed immediately rather than halfway down the question sequence. As well, if something is misconfigured, `Deploy MicroCloud` can error out and return to the submenu selection page so the user can fix the configuration.