- Add sepa_debit to payment_method_types for credit purchases
- Add sepa_debit to subscription checkout sessions
- Handle payment_intent.processing webhook for SEPA status tracking
- Add blueprint article analyzing payment options (Stripe vs LSV+/FinTS)
SEPA offers lower fees (0.8% vs 1.5%+€0.25) for DACH customers.
Payments are confirmed 3-14 days after checkout (bank processing).