Add Ukrainian translation

[denusbtw]

Description

Added Ukrainian (uk) translation for all user-facing strings.
Created locale/uk/LC_MESSAGES/django.po file and verified compilation using django-admin compilemessages.

Related Issue

N/A – this is a new contribution (translation enhancement).

Motivation and Context

Adds support for Ukrainian language to improve accessibility for Ukrainian-speaking users.

How Has This Been Tested?

Compiled translation files locally with: django-admin compilemessages and verified that translations load correctly when LANGUAGE_CODE = "uk".

Screenshots (if appropriate):

N/A

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• I have run the pre-commit run command to format and lint.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• I have added my name and/or github handle to AUTHORS.rst
• I have added my change to CHANGES.rst
• All new and existing tests passed.