mail_outbound_static

Purpose

Allow outbound emails to use a configurable From address while enforcing RFC-compliant sender handling and domain whitelisting.

Features

ir.mail_server: Adds Email From and domain whitelist fields to control when the original From header is replaced during delivery.
ir.mail_server: Validates configured Email From addresses and whitelisted domains to ensure only properly formatted values are saved.
ir.mail_server: Automatically chooses the outgoing mail server based on the sender’s domain, falling back to the first available server by sequence when no match is found.
mail delivery: Updates Return-Path to mirror the substituted From address when bounce handling is disabled, keeping headers aligned.