Convert to new Region and Culture approach

[Luisav1]

For phetsims/joist#958 to use localizedImageProperty in Area Model Multiplication and Area Model Algebra.

[Luisav1]

I'm unsure whether to use generic or specific names for image files. Initially, I opted for GameHomeScreenIcon and removed the Variables or Generic prefix to generalize, since they're utilized within their own AMA and AMM sims. However, considering their usage within area-model-common alongside specific elements like VariablesScreen or GenericScreen, I'm unsure about the appropriate naming convention. @pixelzoom Could you provide guidance?

[pixelzoom]

I'm unsure whether to use generic or specific names for image files. ... @pixelzoom Could you provide guidance?

Wow. The classing naming (and documentation) in area-model-common sure is confusing. There are bigger problems here than the image filenames. So I recommend that you just use the existing image filenames, and not try to sort out the naming problem.

I wasn't sure if the R&C conversion was ready for review yet, so I didn't take a look. Feel free to assign back to me for review when you're done.

[Luisav1]

Thanks @pixelzoom. I've reverted the renaming commits done above to use the old image filenames. This is now ready for your review.

[pixelzoom]

Conversion looks good.

I found a couple of things in area-model-common that were vestigial (GameScreenIcon, JugglerPortrayal), and deleted them in the above commit. Back to @Luisav1 in case there's anything else that is vestigial that I'm not aware of. Feel free to close if there's nothing else to do.

[Luisav1]

Thanks for tidying up the vestigial items in area-model-common. Sorry for missing those files initially, I found no other vestigial items. Closing.