Consider moving part configs to separate files to ease difficulty config; localization

[z-adams]

Putting part configs in the .sturdy.gltf sounded like a good idea at first, but considering things like difficulty settings, language localization, and upgrades, it would be better to put part configs in separate files.
It sounds like we're approaching some kind of patch-based system for machine configs. The configs that BlueprintMachine store will patch over the configs of the PrototypeMachine. It might make sense to make some functions that easily combines these configs.

#57 (review)