Cleaning up mdbook

[nyurik]

A lot of book content cleanup, making it a bit shorter and "logical" (whatever that even means)

To try, run just mdbook

cc: @sharkAndshark

[sharkAndshark]

Looks great! I love this version.
And I'm thinking something these days. I dont' know. Is it ok to add a get started section before runing section, to clarify the easiest and common ways to give martin a taste. It's for the person who is interested but has no time or enough skills.
Like:

[nyurik]

sure, i'm all for some tutorial. Moreover, i think that tutorial will be far easier to do without docker or any other fancy install - instead simply download the binary from the release dir. That said, we still don't have a good story on how to serve static assets (e.g. maplibre lib, stylesheet, fonts,...)... So still TBD

[nyurik]

I think i will self merge this one and this way you can propose a change to it more easily