Use an external service for handling translations

[gunta]

Currently we employ regular Pull Requests for managing translations, which is suboptimal for regular translators.

I recommend adopting a platform like Transifex for easier string handling, empowering those who are not developers to contribute translations more easily.

I've successfully used Transifex for my own STF project and noted its use in other open-source projects like Sentry. I would say it is the de-facto solution for OSS projects.