A progress page for the third edition

The third edition now has a progress page — one place to see everything the revision needs and how much of it is done, section by section, with progress bars to match.

Behind it is a single file: progress.asc, a plain AsciiDoc checklist at the root of the repository. It distills the chapter-by-chapter inventory from REVISION_PLAN.md into concrete tasks: the policy decisions that gate everything else, the book-wide sweeps like master → main and SHA-256, a section for every chapter and appendix, and the brand-new material Git 3.0 calls for.

The file is the source of truth, and it is edited by hand. Checking a task off means changing [ ] to [x]; adding a task means adding a line. When new work turns up — and it will — it gets a new line or a new section, and the page picks it up on the next build. Because it is standard AsciiDoc checklist syntax, the same file renders as tick-boxes right in the repository on GitHub.

At the time of writing the counter sits at 5 of 75 tasks — the project scaffolding is done, and the writing is about to begin. Watch the bars fill in on the progress page, and if you spot work that belongs on the list, progress.asc is one pull request away.