Multi-language translation support

Lack of translations (especially Spanish) is blocking adoption in some communities. Even simple terms like "Send and receive" create a cultural barrier that leads to rejection.

Bitcoin circular economy projects in Chile and Peru are waiting on Spanish translation to implement Alby Go & Hub in their local beach communities.

A possible implementation:
Use expo-localization + i18n-js (Expo's standard approach): create a /locales folder with JSON files per language (en.json, es.json, etc.), extract hardcoded strings, and wrap text with t() function. The app auto-detects device language.

I'm willing to contribute to this implementation when the time is appropriate,
As well as the initial Spanish translation, translations can be done very easily to all languages with LLMS anyway.