Revert "fix: resolve PHPStan static analysis warnings"

This reverts commit 2d3e4b4a95.

app/Models/ServerGroup.php

@@ -4,17 +4,7 @@ namespace App\Models;
 
 use Illuminate\Database\Eloquent\Model;
 use Illuminate\Database\Eloquent\Relations\HasMany;
-use Illuminate\Database\Eloquent\Casts\Attribute;
 
-/**
- * App\Models\ServerGroup
- *
- * @property int $id
- * @property string $name 分组名
- * @property int $created_at
- * @property int $updated_at
- * @property-read int $server_count 服务器数量
- */
 class ServerGroup extends Model
 {
     protected $table = 'v2_server_group';
@@ -33,14 +23,4 @@ class ServerGroup extends Model
     {
         return Server::whereJsonContains('group_ids', (string) $this->id)->get();
     }
-
-    /**
-     * 获取服务器数量
-     */
-    protected function serverCount(): Attribute
-    {
-        return Attribute::make(
-            get: fn () => Server::whereJsonContains('group_ids', (string) $this->id)->count(),
-        );
-    }
 }