Retranslate Auto Responder Translation

Replaces a translation's copy with a fresh translation of the original as it stands: queues a pass over every one of its variants that rewrites the subject, preview line, content, and annotation from the original variant, including anything edited by hand, and writes the result straight onto the variant rather than leaving a draft. Drafts waiting to be reviewed are discarded. Any variant added to the original since the translation was made is cloned and translated too, along with its template when that has no version in the language yet.