Function wire_http_sse_relay 

pub fn wire_http_sse_relay<E, F, Fut, ErrFmt>(
    run_starter: RunStarter,
    encoder: E,
    ingress_rx: UnboundedReceiver<RuntimeInput>,
    config: HttpSseRelayConfig<F, ErrFmt>,
) -> Receiver<Bytes>
where
    E: Transcoder<Input = AgentEvent> + 'static,
    E::Output: Serialize + Send + 'static,
    F: FnOnce(Sender<Bytes>) -> Fut + Send + 'static,
    Fut: Future<Output = ()> + Send,
    ErrFmt: Fn(String) -> Bytes + Send + 'static,

Wire an HTTP SSE relay for a single agent run.

Sets up the full pipeline: runtime endpoint -> protocol transcoder -> transport binding -> SSE server endpoint, then spawns the relay and event pump tasks.

Returns the SSE byte receiver to feed into an HTTP response body.