Implement equality check

[frectonz]

Potential implementation of #229 I used the regular rust way of PartialEq and Eq to check for equality.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 68.75000% with 20 lines in your changes are missing coverage. Please review.

Project coverage is 83.30%. Comparing base (7dce963) to head (c3e7795).

Files	Patch %	Lines
core/src/ast.rs	38.09%	13 Missing :warning:
core/src/num/unit.rs	40.00%	3 Missing :warning:
core/src/lexer.rs	71.42%	2 Missing :warning:
core/src/scope.rs	0.00%	2 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #275 +/- ## ========================================== - Coverage 83.37% 83.30% -0.07% ========================================== Files 52 52 Lines 14668 14721 +53 ========================================== + Hits 12229 12264 +35 - Misses 2439 2457 +18 ```

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[printfn]

Wow, you’re on a roll with all the things you’ve been implementing recently. Thanks so much for all your work!! I’ve left a small comment to improve the equality checks a bit, but otherwise your implementation looks excellent!

[frectonz]

thanks for the kind words :pray: and btw i also implemented inequality

[frectonz]

Comparisons of different units is now implemented 🎉