Add announce address detection to internal/mail/router.go following the same pattern as isListAddress/parseListName and isQueueAddress/ parseQueueName. Added: - isAnnounceAddress(address string) bool - returns true for 'announce:' prefix - parseAnnounceName(address string) string - extracts channel name - ErrUnknownAnnounce error variable (gt-pn2fq) 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>