[elistbox] enhance selection movement with wrap-around functionality

[DimitarCC]

This pull request refactors and improves the navigation logic in the eListbox::moveSelection method, especially for multi-column listboxes. The main changes enhance the behavior of left/right movement within rows and add wrap-around support for page up/down navigation, ensuring a more intuitive and robust user experience.

Navigation improvements within rows:

• Improved left movement logic to properly wrap to the last column of the current row when wrap-around is enabled, and to handle non-selectable items more reliably (lib/gui/elistbox.cpp).
• Improved right movement logic to wrap to the first column of the current row when wrap-around is enabled, with consistent handling of non-selectable items (lib/gui/elistbox.cpp).

Wrap-around support for page navigation:

• Added support for wrapping from the first page to the last page when pressing Page Up or Prev Page, moving to the last selectable entry if wrap-around is enabled (lib/gui/elistbox.cpp).
• Added support for wrapping from the last page to the first page when pressing Page Down or Next Page, moving to the first selectable entry if wrap-around is enabled (lib/gui/elistbox.cpp).