- Buffer DATA body until CRLF.CRLF terminator — fixes 502-on-every-body-line bug
- SMTP_OPEN_RELAY=1: AUTH accepted (235), RCPT TO accepted for any domain,
full DATA pipeline with queued-as message ID
- Default (SMTP_OPEN_RELAY=0): credential harvester — AUTH rejected (535)
but connection stays open, RCPT TO returns 554 relay denied
- SASL PLAIN and LOGIN multi-step AUTH both decoded and logged
- RSET clears all per-transaction state
- Add development/SMTP_RELAY.md, IMAP_BAIT.md, ICS_SCADA.md, BUG_FIXES.md
(live-tested service realism plans)
