Whats Next? 0.20.0 - Interface localization foundation

- First-run interface language chooser: English / Русский / Українська.
- English is the default language.
- Language can be changed from Settings and is stored in WhatsNextUserData.
- Added bundled RussianNames database (798 sanitized public item-name entries), separate from user data.
- EN interface displays Russian item equivalents when present in the bundled database.
- RU/UA interface displays English item equivalents from the bundled English database.
- Item-level / upgrade-track names are intentionally not translated.
- Craft filter MATERIAL / TYPE renamed to EQUIPMENT TYPE: MAIL is an armor type, not a material.
- Added bilingual equivalent line to loot tooltips without changing Blizzard item-level tooltip data.
- Added compact translations to major Tasks, Loot, Equipment, Tank Assistant, Calendar and Settings UI.
- Language changes reload UI to guarantee every frame is rebuilt consistently and prevent mixed-language state.
