Show HN: Nuvrail – make an AI agent ask before it sends, moves or deletes email

Nuvrail is an approval layer that sits between an AI agent and a real mail server, presenting a normal IMAP/SMTP interface while staging every write (moves, deletes, flag changes, outbound sends) for a human to approve or reject with one tap; reads pass through instantly. EXPUNGE and CLOSE are never forwarded, and a local Docker Compose setup runs the approval UI, REST API, and IMAP/SMTP proxies on localhost for evaluation.