fix: resolve PHPStan static analysis warnings

app/Http/Middleware/CheckForMaintenanceMode.php

@@ -2,16 +2,17 @@
 
 namespace App\Http\Middleware;
 
-use Illuminate\Foundation\Http\Middleware\CheckForMaintenanceMode as Middleware;
+use Illuminate\Foundation\Http\Middleware\PreventRequestsDuringMaintenance;
 
-class CheckForMaintenanceMode extends Middleware
+class CheckForMaintenanceMode extends PreventRequestsDuringMaintenance
 {
     /**
-     * The URIs that should be reachable while maintenance mode is enabled.
-     *
-     * @var array
+     * 维护模式白名单URI
+     * @var array<int, string>
      */
     protected $except = [
-        //
+        // 示例：
+        // '/api/health-check',
+        // '/status'
     ];
 }