Feature/language config integration

This Pull Request introduces the integration of the language configuration feature into the application. Changes included:

Backend

Added API endpoints for managing available languages and their configurations.

Frontend

Created a Zustand store to centralize language state management.

Integrated the store with the backend endpoints to ensure real-time synchronization of language settings across the application.

Purpose To enable flexible and centralized language management, improving internationalization support and providing a better user experience.

Testing steps

Open the application and navigate to the language settings.

Change the language and verify that the update reflects across the entire application.

Confirm that the selected language is persisted after a refresh.