Review the latest set of changes in the “short user manual”

The Tor Short User Manual is appears to be written in mentat rather than human, and I find the section ordering and formatting confusing.

I think it could benefit from a Table of Contents, and a few screenshots of what the TBB startup process looks like, and what the various failure modes look like (like blocking and bridge configuration). It probably should also include a brief description of the privacy properties you get from the Tor Browser (See #5294 (moved)), and some hints on what the new Tor Browser branding actually looks like on your taskbar (so you don't use the wrong browser).

Also, the GPG verification steps need to be improved to contain screenshots, moved to an "Advanced" section, or simply removed. How does one bootstrap trust in the downloaded GPG binary itself, anyway? Seems like useless noise to even mention GPG verification at that point.