Replace mypy with zuban #118
Description
From Zuban's README:
Zuban is a high-performance Python Language Server and type checker implemented in Rust, by the author of Jedi. Zuban is 20–200× faster than Mypy, while using roughly half the memory and CPU compared to Ty and Pyrefly. It offers both a PyRight-like mode and a Mypy-compatible mode, which behaves just like Mypy; supporting the same config files, command-line flags, and error messages.
Is your improvement request related to a problem? Please describe.
There are no outstanding issues that this replacement would fix, but I'm very keen on trying out new technology, especially the ones that re-imagine existing well-established tools, aiming for a smaller footprint (memory and CPU usage).
Describe the improvement you'd like
Replace MyPy with Zuban as the type-checker for this project.
Additional context
We need to be careful with support for pydantic, since we currently depend on the pydantic.mypy extension - which I'm not sure if Zuban supports.