Enabled Translations / Languages

This would be a section in the admin settings to configure which translations to make available for Disciple Tools users.
This would reduce the list down to just a few and make it easier for users to switch between languages or to select their language.
It will also let us display a shorter list for field translations.

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In the custom lists, there is currently a Language Options. This isn't synced to the translations list and was more geared for the contact field. I think we'll need to build a new settings section for the enabled translations.

Start by reviewing the existing custom-list Language Options and the current translations list, since the issue says they are not synchronized. Define how a new admin settings section should configure enabled translations and how that list should affect user language selection and field translations; the work is done when both uses consistently show only the configured languages.

Written by the indexing model from the issue text.