The Desktop update check asks api.github.com for main's tip before it asks
Git. The windows GUI update driver only redirected Git transport, and the
app's probe Git runs with GIT_CONFIG_GLOBAL=/dev/null, so it never saw the
redirect. When real GitHub main equalled the installed OLD commit, the app
reported no update and the leg waited 3 minutes for an Update now button
that could not appear.
Install the staged-main probe the macOS and Linux source legs already use.
It wraps Git with the staged insteadOf rewrite and selects --branch main,
so the real checker, UI and updater still run against serve.git.
c68f80664e
