[RIG 25w02a Updater] Support changes from 25w09a

[Seeloewen]

Previously, unicode escapes and new lines (\u and \n) as well as some other escapes were not possible anymore.
Snapshot 25w09a finally added support back, making some of the conversion the software does obsolete. The software will ask whether to convert for 25w02a or 25w09a.