✨ template: package C++ Python bindings

[lalmei]

Summary:

• Adds meson-python build metadata for generated C++ pybind11 wheels.
• Tags Meson install artifacts so wheels include the extension and runtime library without CLI/header installs.
• Adds generated make build-wheel and make check-wheel targets plus README/development docs.

Validation:

• uv run pytest -c=config/pytest.ini tests/test_template/test_cpp_template.py --no-cov
• make check
• make check-docs
• generated sample-cpp: make setup, make test, make format-check, make check-wheel
• inspected generated wheel contents for extension, relocated runtime library, and license metadata