fix: missing "user left" system message after omnichannel room forward (#41480)

Author: KevLehman

.changeset/livechat-forward-ul-message.md

@@ -0,0 +1,5 @@
+---
+'@rocket.chat/meteor': patch
+---
+
+Fixes an issue where the "user left" system message could be added to an Omnichannel conversation only after the forwarding process had already finished, causing it to appear out of order in the conversation history

apps/meteor/server/lib/omnichannel/RoutingManager.ts

@@ -371,12 +371,11 @@ export const RoutingManager: Routing = {
 	async removeAllRoomSubscriptions(room, ignoreUser) {
 		const { _id: roomId } = room;
 
-		const subscriptions = await Subscriptions.findByRoomId(roomId).toArray();
-		subscriptions?.forEach(({ u }) => {
-			if (ignoreUser && ignoreUser._id === u._id) {
-				return;
+		for await (const { u } of Subscriptions.findByRoomId(roomId, { projection: { u: 1 } })) {
+			if (ignoreUser?._id === u._id) {
+				continue;
 			}
-			void removeAgentFromSubscription(roomId, u);
-		});
+			await removeAgentFromSubscription(roomId, u);
+		}
 	},
 };