## Bug

The WebSocket endpoint for `/v1/responses` requires `model` as a **URL query parameter** (`fastapi.Query(...)`), but the [OpenAI WebSocket spec](https://platform.openai.com/docs/guides/websocket-mode) sends `model` inside the `response.create` message payload, not as a query param.

This means any spec-compliant client (e.g. [Codex CLI](https://github.com/openai/codex)) connecting to `ws://.../v1/responses` without `?model=` gets a **403 Forbidden** — FastAPI rejects the missing required query param before auth even runs.

## Root cause

In `litellm/proxy/response_api_endpoints/endpoints.py`:

```python @router.websocket("/v1/responses") @router.websocket("/responses") async def responses_websocket_endpoint( websocket: WebSocket, model: str = fastapi.Query( ..., description="The model to use for the responses WebSocket session." ), user_api_key_dict=Depends(user_api_key_auth_websocket), ): ```

`model: str = fastapi.Query(...)` makes it a required URL query parameter. When a client connects without it, FastAPI returns 403 at the framework level before the handler or auth logic runs.

## Reproduction

```python import asyncio from websockets.asyncio.c…