[rejected AI] fix(json): support os.PathLike serialization and guard dataclass class type in DefaultJSONProvider

[vjymisal0]

Summary

1. os.PathLike Serialization Support:
   • DefaultJSONProvider._default now supports os.PathLike objects (e.g. pathlib.Path, pathlib.PurePosixPath, pathlib.PureWindowsPath) by serializing them as strings (str(o)), matching standard library behavior and common web framework patterns.
2. Dataclass Class Type Guard:
   • dataclasses.is_dataclass(o) returns True for both dataclass instances and dataclass class types. When passed a dataclass class, dataclasses.asdict(o) raised TypeError: asdict() should be called on dataclass instances, not on classes. Added and not isinstance(o, type) to properly allow it to fall through to the standard JSON serializability TypeError.

Tests

• Added unit tests test_pathlike_serialization and test_dataclass_class_raises_typeerror in tests/test_json.py.
• All 495 pytest unit tests pass cleanly.

[davidism]

https://palletsprojects.com/contributing/llm-ai

[davidism]

I do not want to add more types to this. I do not care that the error on invalid data is different for some data, it's invalid regardless and would be fixed not caught.