Add basic subuser listing for servers

app/Transformers/Api/Client/SubuserTransformer.php

@@ -0,0 +1,55 @@
+<?php
+
+namespace Pterodactyl\Transformers\Api\Client;
+
+use Illuminate\Support\Str;
+use Pterodactyl\Models\Subuser;
+
+class SubuserTransformer extends BaseClientTransformer
+{
+    protected $availableIncludes = ['permissions'];
+
+    /**
+     * Return the resource name for the JSONAPI output.
+     *
+     * @return string
+     */
+    public function getResourceName(): string
+    {
+        return Subuser::RESOURCE_NAME;
+    }
+
+    /**
+     * Transforms a User model into a representation that can be shown to regular
+     * users of the API.
+     *
+     * @param \Pterodactyl\Models\Subuser $model
+     * @return array
+     */
+    public function transform(Subuser $model)
+    {
+        $user = $model->user;
+
+        return [
+            'uuid' => $user->uuid,
+            'username' => $user->username,
+            'email' => $user->email,
+            'image' => 'https://gravatar.com/avatar/' . md5(Str::lower($user->email)),
+            '2fa_enabled' => $user->use_totp,
+            'created_at' => $model->created_at->toIso8601String(),
+        ];
+    }
+
+    /**
+     * Include the permissions associated with this subuser.
+     *
+     * @param \Pterodactyl\Models\Subuser $model
+     * @return \League\Fractal\Resource\Item
+     */
+    public function includePermissions(Subuser $model)
+    {
+        return $this->item($model, function (Subuser $model) {
+            return ['permissions' => $model->permissions->pluck('permission')];
+        });
+    }
+}