Fourth step in making user status `away` a deprecated way to access
`presence_enabled` for clients supporting older servers, and
checkpoint commit prior to deleting the `status` field from the
UserStatus model.
Part of transitioning from 'unavailable' user status feature to
'invisible mode' user presence feature.
When a user toggles a status update for `away=True|False`, we now update
their `presence_enabled` setting to match (`away!=presence_enabled`).
First step of making user status `away` updates a deprecated way to
access presence_enabled for clients supporting older servers, and
checkpoint commit before migrating users with a current UserStatus
of `status=AWAY` to have their `presence_enabled` set to `False`.
Note that when user status `away` is updated, we now send 4 events:
user_status, user_settings, presence, and update_global_notifications.
Also, this means that these updates change the UserPresence.status
value, which impacts the test for importing and exporting user
information.
Part of transitioning from 'unavailable' user status feature to
'invisible mode' user presence feature.
We need to move this function to a separate actions file specifically
for `user_status` because otherwise we will have a circular import
between `actions/user_settings.py` and `actions/presence.py` in an
upcoming commit.
Prep commit for migrating "unavailable" user status feature to
"invisible" user presence feature.