Previously a brand-new repo (git init, no commits) surfaced `git stash
create: exit status 128: You do not have the initial commit yet` from
deep inside the archive helper. Now the publish flow detects this case
via `git rev-parse --verify HEAD` up front and prints "no commits in
repository; run `git add . && git commit` before publishing". Also
updates the init flow's hint to mention `git init && git commit` so
users aren't misled into thinking `git init` alone is enough.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
4c0104619e