feat: localize widget labels and initial states

[V3RON]

This PR adds first-class localization support for Voltra home screen widgets, so app developers can ship widget names, descriptions, and pre-rendered initial states in multiple languages without maintaining separate native localization code by hand.

What this means for Voltra users

• you can now provide localized displayName and description values in the Expo plugin config using locale maps instead of a single string
• you can localize initialStatePath, so the widget’s first rendered state can match the user’s language before the app updates it
• iOS and Android now pick the best localized value automatically from the device locale, with fallback behavior that matches user expectations
• Android supports script-based locale tags such as zh-Hans, so widget picker strings can be packaged correctly for those locales too

User-facing behavior

• Voltra first tries an exact locale match
• if there is no exact match, it falls back to a language-only match
• if there is still no match, it prefers an English locale such as en or en-US
• if no English locale exists, it uses the first configured locale

Included in this PR

• Expo plugin support for localized widget labels and descriptions on iOS and Android
• localized pre-rendered widget initial states
• native iOS and Android locale selection helpers
• validation and tests for locale keys and fallback behavior
• example config updates and docs describing how to configure localization

Testing

• npm test --workspace @use-voltra/expo-plugin
• npm run lint --workspace @use-voltra/expo-plugin
• npm run build --workspace @use-voltra/expo-plugin