chore: If auth expired return false in authenticate method

Implements #728

Author: sparkison

app/Services/PlaylistService.php

@@ -422,6 +422,11 @@ public function authenticate($username, $password): array|bool
             ->first();
 
         if ($alias) {
+            // If alias found but expired, treat as not found
+            if ($alias->isExpired()) {
+                return false;
+            }
+
             return [
                 $alias,
                 'alias_auth',