uv-build: The uv build backend

uv-build is the official PEP 517 build backend for uv, the fast Python package and project manager. It enables uv to efficiently create source distributions and binary wheels for Python projects. The package is a slimmed-down version of uv itself, containing only the necessary components for the build backend functionality. It is under active development with frequent releases, often multiple times a week, ensuring tight integration and performance with the main uv tool.