fix: switch to xserver database with UTF-8 data

- Change default database from x_server_mobile to xserver
- Add 007_xserver_init.sql initialization script
- Companies data now correctly encoded in UTF-8:
  - 合塑 (hesu)
  - 新友合 (xinyouhe)
  - 派卡 (paika)
  - 斯玛特 (simate)
  - magic bridge Auto (mbaf)
- Company Feishu apps properly configured

The key fix is to execute SQL directly inside the MySQL container
using heredoc to avoid charset conversion issues during transfer.

Usage:
docker exec 1Panel-mysql-409s mysql -uroot -p'mysql_xEsdPa' --default-character-set=utf8mb4 xserver < 007_xserver_init.sql

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/config/database.php

@@ -7,7 +7,7 @@ return [
             'driver' => 'mysql',
             'host' => getenv('DB_HOST') ?: 'mysql',
             'port' => getenv('DB_PORT') ?: 3306,
-            'database' => getenv('DB_DATABASE') ?: 'x_server_mobile',
+            'database' => getenv('DB_DATABASE') ?: 'xserver',
             'username' => getenv('DB_USERNAME') ?: 'root',
             'password' => getenv('DB_PASSWORD') ?: '123456',
             'unix_socket' => getenv('DB_SOCKET') ?: '',