The shim branch was only copying __init__.py from each package,
which dropped Python source files needed for CFFI builds (build.py,
colors.py, defines.py, enums.py, version.py) and extra packages
like pyray. It also dropped project dependencies like cffi.
- Copy all .py files from the main module, not just __init__.py
- Copy extra packages listed in packages.find.include
- Preserve project dependencies in generated pyproject.toml
