perf: Fetch auth chain events in parallel

src/api/server/event_auth.rs

@@ -1,7 +1,10 @@
 use std::{borrow::Borrow, iter::once};
 
 use axum::extract::State;
-use conduwuit::{Err, Event, Result, info, utils::stream::ReadyExt};
+use conduwuit::{
+	Err, Event, Result, info,
+	utils::stream::{BroadbandExt, ReadyExt},
+};
 use futures::StreamExt;
 use ruma::api::federation::authorization::get_event_authorization;
 
@@ -64,7 +67,9 @@ pub(crate) async fn get_event_authorization_route(
 		.auth_chain
 		.event_ids_iter(&body.room_id, once(body.event_id.borrow()))
 		.ready_filter_map(Result::ok)
-		.filter_map(|id| async move { services.rooms.timeline.get_pdu_json(&id).await.ok() })
+		.broad_filter_map(
+			|id| async move { services.rooms.timeline.get_pdu_json(&id).await.ok() },
+		)
 		.then(|pdu| services.sending.convert_to_outgoing_federation_event(pdu))
 		.collect()
 		.await;