The fourth leg of build-and-test.yml, in the shape of the Android one:
an image workflow that builds docker/windows and pushes it tagged by
the directory's tree id, and a job inside that image that lints the
Windows target — the only place the cfg(windows) branches are ever
compiled by CI — builds, runs the smoke tests docs/windows.md §6
specifies, packages, installs and uninstalls under Wine, and uploads
the installer. Every step was run by hand in the same container first.
The spec's open list closes with this: the four §3.2 items, the
licence page, and the leg. What remains is what Wine cannot show, and
§10 now lists it as the first real Windows run's checklist.