git squash commits on main branch

squash-on-main.sh

# this should get everything down to a single commit
#
git checkout --orphan tmp-main
git commit -m "initial commit"
# move the local branch
git branch -f main
git checkout main
# delete the temp branch
git branch -d tmp-main
# git push --force

# this one leaves the initial commit in place, but squashes everything else
git reset --soft $(git rev-list --max-parents=0 HEAD)
git commit -m "initial release"
# git push --force