feat(member): enhance product info processing and add new utility methods

- Updated `getProductInfo` method to return processed product information using `buildEffectiveProductInfo`.
- Introduced new private methods for building effective product info, resolving software account levels, and checking special TikTok account status.
- Refactored platform string handling with `appendPlatform` method to ensure unique and sorted platform entries.
- Updated platform name mappings in `PlatformService` for consistency with new naming conventions.

app/api/model/DySpecialPlatforms.php

@@ -0,0 +1,36 @@
+<?php
+declare(strict_types=1);
+
+namespace app\api\model;
+
+use think\Model;
+
+/**
+ * 用户单独平台权限模型（对应 dy_special_platforms 表）
+ *
+ * 该表用于覆盖套餐默认平台集合，并补充少量用户级能力开关。
+ */
+class DySpecialPlatforms extends Model
+{
+    // 与 acgpmw 保持一致，特殊平台权限存放在 member 库。
+    protected $connection = 'dbmember';
+
+    protected $name = 'dy_special_platforms';
+
+    protected $pk = 'id';
+
+    protected $autoWriteTimestamp = false;
+
+    /**
+     * 获取当前用户启用中的特殊平台配置。
+     *
+     * @param int $userid 用户ID
+     * @return self|null
+     */
+    public static function findActiveByUserid(int $userid): ?self
+    {
+        return self::where('userid', $userid)
+            ->where('disabled', 0)
+            ->find();
+    }
+}