Canonical receipt email (MAIL-03).
Sent when a one-off or subscription payment succeeds. This module does
NOT attach a PDF — the PDF-bearing variant is Accrue.Emails.InvoicePaid
(Plan 06-06). Both are registered in Accrue.Workers.Mailer dispatch.
Accrue.Emails.PaymentSucceeded is a legacy alias retained for Phase 1
back-compat; downstream code should dispatch by atom (:receipt).
Summary
Functions
Returns the raw MJML template. Useful for debugging rendering issues.
Safely render the MJML template using Phoenix.HTML