git-prune: remove all remotely deleted branches & get latest master/main

git-prune.sh

function git-prune() {
  # Determine the default branch (main or master)
  local branch
  branch=$(git symbolic-ref refs/remotes/origin/HEAD 2>/dev/null | sed 's@^refs/remotes/origin/@@')

  # Fallback if detection fails
  if [ -z "$branch" ]; then
    branch="master"
  fi

  git checkout "$branch"
  git fetch -p
  git pull
  git branch -vv | awk '/: gone]/{print $1}' | xargs -r git branch -d -f
}