Dark/Light Mode toggle issue

The dark/light mode toggle does not work at the moment. It works for the editor but not the rest of the application.

Kindly submit a pull request and ensure the theme toggle applies globally across all components, not just the editor.

Kindly make sure to:

- Test the toggle with all major UI components

- Verify that the theme preference persists across page refreshes

- Check that the theme is applied consistently to headers, sidebars, modals, and any other UI elements

- Include screenshots/screen recording of the fix working

Thanks!