a43c89c01b
Adds `gt orphans kill` subcommand that permanently removes orphaned commits by running `git gc --prune=now`. Flags: - --dry-run: Preview without deleting - --days N: Kill orphans from last N days (default 7) - --all: Kill all orphans regardless of age - --force: Skip confirmation prompt Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>