Create implicit scope manager

[markehammons]

Implicit scope (the idea of a scope that is tied to a runtime object) is something that could be/would be massively helpful for Slinc. It would allow an upcall pointing to a lambda to be collected once the lambda (and the pointer) has been garbage collected.

[markehammons]

https://docs.oracle.com/en/java/javase/19/docs/api/java.base/java/lang/ref/Cleaner.html

This should be sufficient as a base.