Add Persian (per) localization support with a new per.json translation file and updated StringKeys.cs constants.

[Mahantor]

Description

Add Persian (per) localization support to Winhance. This includes a new per.json translation file with complete Persian translations for all UI strings, and updates to StringKeys.cs constants to support the new language

Type of Change

• 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 not work as expected)
• Documentation update
• Code refactoring (no functional changes)
• Performance improvement
• Build/CI configuration change

Related Issues

Testing Performed

Manually tested by switching the application language to Persian (per) and verifying all UI strings display correctly. Also tested other languages to ensure no regression.

• Unit tests added/updated
• Manual testing performed
• Regression testing performed

Screenshots/Videos

Checklist

• My code follows the code style of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

Additional Notes

This PR adds Persian language support. No breaking changes. All existing functionality remains unchanged.