Auto-unhiding of mouse cursor causes asynchronization with DisplaySettingsInterface

[MarkOates]

When working in windowed mode and using al_hide_mouse_cursor(true), sometimes the mouse cursor will become unhidden by the OS, usually when the cursor exits the display window. The AllegroFlare/DisplaySettingsInterfaces/Live mouse_cursor_hidden will not update when this occurs, and sometimes results in more issues with toggle_hide_mouse_cursor().

Ideally, the cursor should unhide when exiting the display, and then re-hide upon entering the display.

• There may be a solution using ALLEGRO_EVENT_MOUSE_LEAVE_DISPLAY (https://liballeg.org/a5docs/trunk/events.html#allegro_event_mouse_leave_display) or similar events
• Switching between fullscreen and windowed should not break the synchronization either.
• Another option is to see if Allegro5 can support polling for the show/hide status of the cursor (though this would mean a polling behavior which is not great.)
• This is currently the behavior on MacOS, and has not been tested on other platforms.