Plain-English docs

The same information as ../technical/, written for anyone who isn't reading code day to day — analogies instead of file:line citations, but nothing invented and nothing simplified into being wrong. Both tracks are required to stay in sync — see ../README.md for the index of both.

• OVERVIEW.md — what the cockpit does, in five steps; the two halves that make it up; why the layout changes shape on different screens (and the real bug that taught us why); and the trust/safety promises this system makes on purpose.
• getting-started.md — the two commands that turn it on.
• learn-more.md — what the pieces are actually built with, explained without jargon, with links to read further.
• making-of.md — the build story so far, growing over time, told without needing to read code.