4deefb52de
- createTransport() called per-send from DB SmtpConfig (Pitfall 3 mitigation — not at startup) - Injects SettingsService to load decrypted SMTP config per tenant - secure/requireTLS mapped from encryption field (ssl-tls / starttls / none) - Auth omitted when username absent (anonymous relay support) - Attachment contentType: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet - Error path rethrows after generic log (T-07-10) so DkvService can run 3-retry backoff (D-16) - Does not import @nestjs-modules/mailer abstractions