Function codex_websocket_event_stream 

pub async fn codex_websocket_event_stream(
    url: &str,
    headers: &HeaderMap,
    body_value: &Value,
    _ctx: &RequestContext,
    traffic: Option<Arc<TrafficCapture>>,
    pool_key: Option<&str>,
    connect_timeout_ms: u64,
    idle_timeout_ms: u64,
    continuation: Option<&ContinuationCandidate>,
) -> Result<CodexWebSocketEventReceiver, CodexError>