This trait is in charge of overseeing the VM’s step usage in contexts where a limited amount of steps are available
for a single execution (which may or not involve other executions taking place in the duration of it ).
This is mostly used in the context of starknet, where contracts can call other contracts while sharing the same step limit.
For the general use case, the default implementation can be used, which ignores resource tracking altogether
For an example on how to implement this trait for its intended purpose check out
BuiltinHintProcessor