Enhance ProcessId from a type alias to a newtype

[roman]

Summary

As the API owner, I want to make sure that the only way a terminateProcess invocation can be made, is that you call a fork function from the library.

Context

Currently, terminateProcess receives any UUID type, we want to make sure that invalid calls to terminateProcess cannot be made

Implementation Notes

Follow the compilation errors once we transform a type to a newtype, behavior of the library should stay the same as this returned value was being treated as an opaque one