stalwartlabs/stalwart ? reverse-engineered prompt

Build me a secure mail and collaboration server that can run for a small team and also scale later if needed. I want it to handle normal email sending and receiving, plus calendar, contacts, and file access in one place, with support for common clients that use IMAP, SMTP, JMAP, CalDAV, CardDAV, POP3, and WebDAV.

Please make it feel production ready, with good defaults for security, spam and phishing protection, user accounts, domains, aliases, and easy configuration for storage and search. It should be straightforward to run locally or in Docker, and it should be clear how to set up TLS, DNS, and admin settings. If anything depends on current best practices or recent protocol details, look up the latest docs online if you need to.

I’d like the whole thing to be reliable, fast, and cleanly organized so it can be used as a real self hosted mail server, not just a demo.