Affected: npm: nodemailer

### Summary

Nodemailer's email-address parser treats an **RFC 5322 comment** `( ... )` inside the domain as a point to **concatenate** the surrounding text, rather than as folding whitespace (CFWS) that **terminates** the domain. Consequently a recipient address such as `user@good-corp.com(x)evil.com` is parsed and **delivered to `good-corp.comevil.com`** (registrable domain `comevil.com`, attacker‑controlled), while a conformant RFC 5322 parser terminates the domain at the comment and reads `good-corp.com`.

An application that decides *whether it is allowed to email a recipient* by parsing/validating the recipient's domain — with a strict RFC 5322 parser (used without inspecting parse defects) or with a naive prefix/substring allow‑list — and then hands the raw address to Nodemailer for delivery, can be induced to send mail to a domain the attacker controls. This is an **Interpretation Conflict (CWE‑436)**, the same class as CVE‑2025‑13033, reached through the RFC 5322 *comment* construct (the "Comments" technique in PortSwigger's *Splitting the email atom* research, which produced a Postfix fix).

Severity is **Moderate**: exploitation requires the app's domain check to disagree with Nodemailer (see **Impact** for exactly which parsers do and do not). Verified end‑to‑end against a real RFC 5321 SMTP server (nodemailer 9.0.6 → `aiosmtpd`).

### Details

Root cause is in `lib/addressparser/index.js`.

1. The tokenizer registers the comment as an operator pair (`Tokenizer.o…