perf(users): Create lazy users in IUserManager::getSeenUsers

Particularly relevant in occ commands/background jobs like the trashbin
expiration which only needs the user ids and not the full information.

Signed-off-by: Carl Schwan <carl.schwan@nextcloud.com>

Author: CarlSchwan

lib/private/User/Manager.php

@@ -845,7 +845,7 @@ public function getSeenUsers(int $offset = 0): \Iterator {
 			foreach ($userIds as $userId) {
 				foreach ($this->backends as $backend) {
 					if ($backend->userExists($userId)) {
-						$user = $this->getUserObject($userId, $backend, false);
+						$user = new LazyUser($userId, $this, null, $backend);
 						yield $user;
 						break;
 					}