This fixes a bug where Explorer would not detect when:
- an implementation used a method to implement a class function in an interface
- an implementation used a class function to implement a method in an interface
- an implementation method used `addr self` when the interface method did not
- an interface method used `addr self` when the implementation method did not
at type checking time. This would then cause a crash at runtime.
Closes#2857
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Co-authored-by: Richard Smith <richard@metafoo.co.uk>
josh11bandRichard Smith
318eb793eb