Add a new ASGI worker type that provides native async support using
gunicorn's own HTTP parsing infrastructure adapted for asyncio.
Features:
- HTTP/1.1 with keepalive support
- WebSocket connections (RFC 6455)
- ASGI lifespan protocol for startup/shutdown hooks
- Optional uvloop support for improved performance
- Full proxy protocol support (inherited from gunicorn)
New configuration options:
- --asgi-loop: Event loop selection (auto/asyncio/uvloop)
- --asgi-lifespan: Lifespan protocol control (auto/on/off)
- --root-path: ASGI root path for reverse proxy setups
Usage: gunicorn -k asgi myapp:app
