Implement compiler checks

[nkakouros]

The original mal compiler implemented checks for various aspects of syntax validity, constraints, etc. These can be found here.

TODO

• [ ] Read up on attack graphs, what they are, what they look like
• [ ] Study the mal language. Here are some resources:
  • [ ] https://github.com/mal-lang/mal-documentation/wiki
  • [ ] https://github.com/mal-lang/exampleLang/
• [ ] Understand the new mal compiler:
  • [ ] Study the mal syntax grammar, see this PR and the .g4 grammar file, until it gets merged.
  • [ ] Understand the visitor pattern of the compiler
• [ ] Implement the validator checks
  • [ ] Understand each check in the original compiler's analyzer
  • [ ] Implement each check in the original compiler's analyzer

[andrewbwm]

It might be useful for the person doing this to also have a look at the Language Graph(https://github.com/mal-lang/mal-toolbox/blob/main/maltoolbox/language/languagegraph.py).