Add multi-language support

🚀 Feature Request

Summary

Enable multi-language support by introducing i18n.

Problem to Solve / User Story

As a Constrainify maintainer and developer, I want to enable translators to add further languages.

Proposed Solution

• Implement internationalization (i18n) support using a dedicated library (e.g. python-i18n.
• Ensure that all text elements are extracted into translation files.
• Provide a mechanism for to integrate new translations (e.g. config dir).

Benefits

• Enables creation of translations into other languages, which enables the creation of translations into other languages, reaching non-English users.
• Makes the application more adaptable.

Possible Drawbacks

• This feature is not compatible with constraints, data model mappings or data. Consequently, the translations produced may lack coherence.

Alternatives Considered

• Keeping the application monolingual and relying on external translation tools.