Spotify Subscription Manager - Full implementation

Steps after upload:
1. Create MySQL database and import schema.sql
2. Update inc/config.php with DB credentials, encryption_key, Telegram bot token and chat id
3. Move inc/config.php outside public_html if possible
4. Optionally install PhpSpreadsheet via Composer and upload vendor/
5. Create an admin account using the provided SQL or run the create_admin.php script
6. Set up a cron job to run: php /home/youruser/public_html/spotify_manager_full/cron_check.php 0
