Update the `unix_listener auth-userdb` configuration in `templates/10-master.conf.j2`. This change switches the socket ownership from `vmail` to the `postfix` user and explicitly sets the group to `postfix`.
This ensures that the Postfix service has the necessary permissions to access the Dovecot authentication socket for user lookups.
Introduces functionality to install and configure Dovecot alongside Postfix to provide IMAP/POP3 services.
Changes include:
- Added tasks to install Dovecot packages (core, imapd, pop3d, lmtpd).
- Added templates for main configuration and conf.d files (auth, master, ssl, mail).
- Defined default variables for protocols, SSL settings, and Maildir location.
- Enabled Postfix SASL and LMTP integration options.
- Added a handler to restart the Dovecot service.
- Updated README.md with the new configuration variables and usage instructions.