Avoid duplicating user-defined enum property names

[wileykestner]

This is a naive attempt at dynamically avoiding name collisions between the generated name for a Schema object's enum property and the name of another, user-defined, Schema type.

Pros: All tests pass (at least when I run them locally with pdm run test) Cons: I have no idea what I'm doing.

This is proposed to advance the discussion, all suggestions and guidance are most welcome.

Resolves #1167 (Allegedly)