PortOne PayPal Integration Test

Setup Instructions:

1. Go to admin.portone.cloud
2. Navigate to Settings → API
3. Copy your PortOne Key and Secret Key
4. Add them to .env.local as PORTONE_API_KEY and PORTONE_SECRET_KEY
5. Make sure you have configured PayPal channel in PortOne dashboard
6. Restart your dev server after updating .env.local