[Feature Request] Display or link to the Usage Guide

[starkle]

Referencing https://grapheneos.org/usage

I think new users may open this app hoping to get an introduction to how to use the OS. Luckily a usage guide has already been written. Just linking to it could be enough, but it would be cool to have the usage guide content display in the app itself, maybe with a pretty table of contents.

The same may be desirable for the FAQ or Features pages for similar reasons.

[oppressor1761]

Or rather https://grapheneos.org