* Fix type errors for ty 0.0.1-alpha.31 upgrade
Add type ignores and fixes for ty's stricter checking:
- Path(None) guards in cli.py
- isinstance checks for ElicitRequestFormParams (URL elicitation support)
- TODO(ty) comments for match/isinstance narrowing bugs
- Method override type ignores for generic covariance
- Starlette Middleware typing workarounds
- Dynamic type construction ignores in json_schema_type.py
* Fix remaining type errors for ty 0.0.1-alpha.31
- Add asserts for optional attribute access in tests
- Add type ignores for dynamic httpx transport internals
- Add TODO(ty) comments for `in` operator on str|bytes
- Add TODO(ty) comments for Starlette Middleware typing
- Use cast for prompt.fn async validation in server.py
* Upgrade ty to 0.0.1-alpha.31
Fixes additional test file type errors discovered after upgrade.