Add multilanguage support with Spanish/English and autodetection

[Javierif]

Implement multilanguage support so AzulClaw can function at least in Spanish and English. The system should autodetect the user's computer language at startup and default to the detected language. In addition, add an option in the settings inside azul_desktop to allow the user to manually choose the language.

Tasks:

• Add language autodetection logic (Spanish/English fallback)
• Integrate locale selection into azul_desktop settings
• Ensure all visible UI strings support both languages
• Consider extensibility for more languages in future

This improvement will make Javierif/AzulClaw accessible to a broader user base.