- Rename guide files: nl.md → nl.codepress.md, en.md → uk.codepress.md
- Add language filtering in scanDirectory() for nl.* and uk.* files/folders
- Update formatDisplayName() to remove language prefixes from display names
- Update getGuidePage() to use new naming convention (en → uk mapping)
- Content with nl. prefix only shows when Dutch language is selected
- Content with uk. prefix only shows when English language is selected
