PRIMO PAY - FULL UPDATE

Includes:
- Admin panel: /admin/
- Merchant panel: /merchant/
- Pay-in / Pay-out details
- Wallet / Withdraw UI
- Merchant ID + Secret Key + password
- Domain/IP origin checks
- bKash payment page: /payment/bKash.php?tx=TX_ID
- Nagad payment page: /payment/Nagad.php?tx=TX_ID
- Payment number rotation by merchant + method + amount
- API: /api/v1/payment-create.php, payment-status.php, payout-create.php, webhook.php
- Premium responsive UI

INSTALL:
1. Create MySQL database.
2. Import database/database.sql first.
3. Import database/merchant_panel_upgrade.sql, database/api_upgrade.sql and database/payment_numbers_upgrade.sql if your database was created from an older version.
4. Edit config/config.php with DB credentials and BASE_URL.
5. Create an admin password hash and insert it into admins.
6. Login at /admin/login.php and create merchants.

IMPORTANT:
The payment page records/allocates payment numbers but does NOT fake provider verification. For real automatic bKash/Nagad settlement, connect an authorized provider API/webhook and verify server-to-server before crediting merchant balance.
