PR CI has one windows-2022 job running a curated explicit file list. Every
other job runs on ubuntu, where a Windows-gated suite self-skips and reports
success -- so an unregistered Windows-gated file executes on no machine and
passes green with nothing to tell the author.
Scans every test file for the win32 suite-level gate spellings in use plus the
.win32.test.* filename, and asserts each one appears in BOTH the
"Test Windows-specific boundaries" vitest argv and WINDOWS_PACKAGE_TESTS: the
classifier decides whether the job runs, the argv decides whether the file
runs. The eight already-unregistered files on main are held in a shrink-only
debt list.