Shared hosting local_node withdraw setup

1. Create a Node.js app with:
   - App root: testtonapp.shajahanabir.top/sender
   - Startup file: send_withdraw.js
2. In the Node.js app, add environment variables:
   - TON_ENDPOINT=https://toncenter.com/api/v2/jsonRPC
   - TON_API_KEY=<optional toncenter api key>
   - TON_MNEMONIC=<optional for selftest only; actual cron uses merchant seed from app settings>
3. Run NPM Install from the Node.js app page.
4. In admin settings set:
   - withdraw sender mode = local_node
   - withdraw node binary = node
   - withdraw sender endpoint = empty
   - withdraw sender token = empty
   - enable withdraw autosend = ON
   - merchant seed (encrypted) = your real TON mnemonic
5. Cron job:
   /usr/bin/php /home/abir/testtonapp.shajahanabir.top/api/cron_auto_withdraw.php

Notes:
- The Node app itself does not need to stay running for payouts; PHP cron calls node directly.
- The start script is only a self-test.
