The redirect out of the archive used a literal '/app.asar/' replace, so the
staged get-windows specifier built with path.join on a Windows packaged build
(...\resources\app.asar\dist\...) was never rewritten and the helper spawn
would still land inside the archive. Mirror the app.asar(?=$|[\\/]) regex
main.ts already uses for the same job, and cover the backslash path in the
test. The dev-tree no-op case folds into the segment-boundary test so the
describe block stays at three cases.
Closes#88468 (with the preceding commit from PR #89633).
45760ac022