fixes #36160 - Redefine append domain names setting

This PR aims to unify the format of host names stored in the database and the way they are displayed.
With this change, the name of the host is always going to be stored with the domain name appended.
The setting formerly named `append_domain_name_for_hosts` is now renamed to `display_fqdn_for_hosts`...

Refs #36575 - Avoid i18n during startup in host name validation

Fixes: 060d2004d786 ("Fixes #20119 - Be more descriptive when validating hostname")

Refs #36575 - Avoid translations during startup on root_pass

Fixes: c4bfd47fc285 ("fixes #3725, #4167 - root password validations, remove default password")

Fixes #36796 - Make host_facts_updated event visible

Refs #36715 - Update fact_names description for facts_hash

Fixes #36715 - Speed up host fact retrieval

Fixes #36104 - Distinguish host events

Fixes #35942 - pass from settings not encrypted

Fixes #36426 - Introduce human-readable host statuses

Fixes #36107 - Suppress warnings from accessing undefined settings

When Foreman is installed without puppet plugin, it still receives
puppet report from installer run. Visiting dashboard then emits a lot of
warning into logs as Foreman tries to access various puppet_* settings.