Add `git proxy run <name>` that sets proxy, runs the associated
command, and auto-restores/unsets proxy on exit or Ctrl-C.
Also fix click.Exit usage for Click 8.x compatibility.
- Move all source files from mytoolkit/ to bin/
- Update entry point and build config in pyproject.toml
- Add pillow and pypdf dependencies
- Update README and .gitignore paths
- Remove unused subprocess import in pdf.py
- Clean up duplicate imports in pdf merge command
Zhengshou Lai