[#386] Preserve variable annotations in `TypeCheck`.

Description

Problem: Variable annotations are discarded while executing the type checker.

Solution: Change wrapWithNotes so that it preserves VarAnns. Some tests were not considering these annotations as well, so they have been changed to correctly test for them.

This is a precondition to solve #386 (closed).

✅ Checklist for your Merge Request

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• Tests (see short guidelines)

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