fix(websocket): configurable WS read idle timeout (WS-01)

src/gateway/routes.rs

@@ -861,6 +861,7 @@ mod tests {
             ws_session_slots: Arc::new(tokio::sync::Semaphore::new(
                 crate::websocket::DEFAULT_WS_MAX_SESSIONS,
             )),
+            ws_idle_timeout: Some(crate::websocket::DEFAULT_WS_IDLE_TIMEOUT),
         };
         let auth_state = Arc::clone(&provider);
         gateway_router()