Monitors constraints to create "contraption" objects and adds callbacks for changes made to contraptions for efficient contraption-aware functionality.

For example, in order to calculate the total mass of a contraption traditionally one would need to iterate over every entity on the contraption and store this information somewhere.

With Contraption Framework (CFW), a callback is run whenever an entity is added to or removed from a contraption and the total mass is added to or subtracted from the total stored in memory on the contraption object.