Documentation suggestions from new user

[askor]

Hey! 😀

I have fresh eyes, so here are some suggestions for improvements to the documentation:

1. Under "Getting help" in the Readme, there should be a link to the Discussions page on GitHub. This project's discussions page is quite active, and I believe it's better for search and search engine indexing to use that for getting help, rather than only pointing to a FAQ and Matrix. Something like "Check FAQ and/or GitHub discussions". Many projects don't use it so I don't immediately check, especially when the readme points elsewhere.
2. The full command list should be very visible somewhere at the top of Key remapping and Keymap pages.
3. There is nothing apart from a few examples, none of which are complete, that describe what to put in brackets in your config to remap all the modes. There is a list of modes, but nothing that says that "Select / Extend mode" maps to [key.select] for instance. This is also confusing as "Select / Extend mode" is below the "Minor modes" in the keymap, shortly leading me to believe that select mode was a minor mode, and mapped to [key.normal.v].
4. The minor modes not being a mode but a normal mode letter to rebind, is not very obvious, and something special about helix. While the remapping page does talk about minor modes, if you are completely new and don't know what minor modes are, you might skip reading that. I believe it would be better for consistency if all modes had their own [key.mode] bind, but it is maybe not a big deal.

I could make a PR with these suggestions, but I thought best to ask first.