Fix Closure evaluation in general

[gp-lnuff]

Currently throws an error if $locales is a Closure

[what-the-diff]

PR Summary

• Improved accuracy in visibility checking
  This change ensures that when checking if something is visible inside the panels, the program now correctly counts the amount of locales (language regions for the software). Before, it was not taking into account all locales correctly which may have led to inconsistent visibility results. More accurate results mean a better user experience across different language versions of the software.

[gp-lnuff]

There were several other places where properties that could be Closures could not be set as Closures, or they could but then they weren't evaluated in some other function that accessed the property, or they couldn't be closures but the getter was evaluating them anyways. I added support for Closure definitions for every property, defined the setters and getters to reflect that, and changed other instances were properties were being accessed direclty instead of evaluated. This should greatly improve flexibility