Add safety to the spotlight search dialog (#9177)

* Add safety to the spotlight search dialog

Fixes https://github.com/vector-im/element-web/issues/22851

This test was triggering the mentioned bug only occasionally because it was dependent on when the search settled: if it settled early then the length was wrong. In testing, the dialog was caught multiple times to have passed the length chat but update to show duplicated results before the test closed the client, indicating a race condition within the tests.

To fix this, we just make sure everything settles before moving on. We do this on unaffected tests too to ensure they don't regress later.

The affected test was "should find group DMs by usernames or user ids".

* Update cypress/e2e/spotlight/spotlight.spec.ts

Co-authored-by: Robin <robin@robin.town>

Co-authored-by: Robin <robin@robin.town>

src/components/views/dialogs/spotlight/SpotlightDialog.tsx

@@ -376,7 +376,9 @@ const SpotlightDialog: React.FC<IProps> = ({ initialText = "", initialFilter = n
                 })),
                 ...roomResults,
                 ...userResults,
-                ...(profile ? [new DirectoryMember(profile)] : []).map(toMemberResult),
+                ...(profile && !alreadyAddedUserIds.has(profile.user_id)
+                    ? [new DirectoryMember(profile)]
+                    : []).map(toMemberResult),
                 ...publicRooms.map(toPublicRoomResult),
             ].filter(result => filter === null || result.filter.includes(filter));
         },