3a542a80f6
The [minimal reproduction](https://gist.github.com/dcreager/fc53c59b30d7ce71d478dcb2c1c56444) of https://github.com/astral-sh/ty/issues/948 is an example of a class with implicit attributes whose types end up depending on themselves. Our existing cycle detection for `infer_expression_types` is usually enough to handle this situation correctly, but when there are very many of these implicit attributes, we get a combinatorial explosion of running time and memory usage. Adding a separate cycle handler for `ClassLiteral::implicit_attribute` lets us catch and recover from this situation earlier. Closes https://github.com/astral-sh/ty/issues/948