RFC-5321 Email Address Parser

address-rfc2821 is a JavaScript/TypeScript library designed for parsing email addresses conforming to RFC-5321 (formerly RFC-821/2821) specifically for the SMTP envelope, found in `MAIL FROM:` and `RCPT TO:` commands. This module focuses on the nuances of envelope addressing, including handling null senders (`<>`) and correctly managing quoted local-parts. Since version 2.0.0, it transitioned from a regex-based parser to one built with Nearley, providing more robust and accurate parsing. It also supports UTF-8 email addresses according to RFCs 5890-5892, providing the domain in punycode when necessary. The current stable version is 2.1.5, with recent updates including the addition of TypeScript type definitions in v2.1.4 and a fix to `isNull()`'s return type in v2.1.5. The library maintains an active release cadence, reflecting ongoing development and maintenance for Haraka mail server components.