FEATURE - SiteSetting to disable user option to hide their profiles and presences (PR #10885)

Implements a site setting to allow admins to disable the ability for individual users to hide the profile or presence to other users.


    let hiddenProfile = this.get(

var has weird scoping issues.

Lots of tests, I love it!

Also this is a bit odd, checking for two different properties. I assume it’s backwards compatibility? Maybe we can add a comment saying so, perhaps with a TODO to remove it in the future.