Refactor the documentation to accurately describe the role as a complete internal mail server stack including Postfix and Dovecot.
Changes include:
- Expanded the description to explicitly list components and internal use cases.
- Added a section clarifying excluded features (antispam/antivirus).
- Reorganized role variables into General and Postfix configuration tables.
- Cleaned up Markdown formatting and removed excessive bold styling.
Luciano Giacchetta
fc1900838b