[model-gateway] move python to binding folder (#13295)

sgl-router/bindings/python/README.md

@@ -0,0 +1,71 @@
+# SGLang Model Gateway Python Bindings
+
+This directory contains the Python bindings for the SGLang Router, built using [maturin](https://github.com/PyO3/maturin) and [PyO3](https://github.com/PyO3/pyo3).
+
+## Directory Structure
+
+```
+bindings/python/
+├── src/                    # Rust source code for Python bindings
+│   └── lib.rs              # PyO3 bindings implementation
+├── sglang_router/          # Python source code
+│   ├── __init__.py
+│   ├── version.py
+│   ├── launch_server.py
+│   ├── launch_router.py
+│   ├── router.py
+│   ├── router_args.py
+│   └── mini_lb.py
+├── Cargo.toml              # Rust package configuration for bindings
+├── pyproject.toml          # Python package configuration
+├── setup.py                # Setup configuration
+├── MANIFEST.in             # Package manifest
+├── .coveragerc             # Test coverage configuration
+└── README.md               # This file
+```
+
+## Building
+
+### Development Build
+
+```bash
+# Install maturin
+pip install maturin
+
+# Build and install in development mode
+cd sgl-router/bindings/python
+maturin develop --features vendored-openssl
+```
+
+### Production Build
+
+```bash
+# Build wheel
+cd sgl-router/bindings/python
+maturin build --release --out dist --features vendored-openssl
+
+# Install the built wheel
+pip install dist/sglang_router-*.whl
+```
+
+## Testing
+
+```bash
+# Run Python tests
+cd sgl-router
+pytest py_test/
+```
+
+## Configuration
+
+- **pyproject.toml**: Defines package metadata, dependencies, and build configuration
+- **python-source**: Set to "." to indicate Python source is in the same directory as pyproject.toml
+- **module-name**: `sglang_router.sglang_router_rs` - the Rust extension module name
+
+## Notes
+
+- The Rust bindings source code is located in `src/lib.rs`
+- The bindings have their own `Cargo.toml` in this directory
+- The main sglang-router library is located in `../../` and is used as a dependency
+- The package includes both Python code and Rust extensions built with PyO3
+- PyO3 types are prefixed with `Py` in Rust but exposed to Python without the prefix using the `name` attribute