odoo/documentation#18187

Created by Julien Pendeville (jupe)

Blocked

label
odoo-dev:17.0-update-subdomain-mailing-jupe
head
f0dd2e5d8536040594d03dbc76eeec85f0b146f9
odoo/documentation
17.0 #18187 missing r+
18.0
saas-18.2
saas-18.3
saas-18.4
19.0
saas-19.1
saas-19.2
saas-19.3
master

[FIX] mail: move subdomain DNS setup from website to inbound mail doc

The inbound mail documentation referred to the subdomain-based method
as "MX record", which was too narrow and confusing. Both CNAME and MX
records are valid options, but CNAME is simpler to set up as it inherits
SPF and other DNS records from the target domain, avoiding extra
configuration for outbound mail authentication.

The setup instructions were also scattered across the website/domain_names
documentation, which is not where users configuring inbound mail would
naturally look.

In email_servers_inbound.rst, the section is renamed to "DNS records"
and consolidated with step-by-step instructions for both Odoo Online
and Odoo.sh, recommending CNAME while keeping MX as a noted alternative.
All cross-references in email_communication.rst, email_servers_outbound.rst,
and domain_names.rst are updated accordingly.

task-6191004