Migrate the existing checker / suggester code to instead use the new validator framework. We need to add,
- Validator for variable - /%[1-9]/ that is insertable and enforced.
We'll need to update the YAML configuration file located here - https://phabricator.wikimedia.org/diffusion/GTWN/browse/master/groups/
Documentation: https://www.mediawiki.org/wiki/Help:Extension:Translate/Validators
Example patch: https://gerrit.wikimedia.org/r/c/translatewiki/+/549930