Tyro

Yanked due to https://github.com/nerfstudio-project/nerfstudio/issues/882.

- Shift to upstream version of `shtab` for tab completion.
- Support classes defined using `attrs` and `pydantic`.
- Minor fixes for typing and docs.

- Type narrowing improvements.
- Strip unsupported tags in PyPI readme.

**Full Changelog**: https://github.com/brentyi/tyro/compare/v0.3.25...v0.3.26

- Fix linting issues caused by missing (but unnecessary) `get_parser()` overloads.

- Default matching improvements for subcommands.
- Fix nested dictionaries.

- Primarily a performance release. Adds more aggressive caching and lazy string formatting; reduces overall overhead of `tyro.cli()` by 3~4x.
- Improves line break handling for parser descriptions.