TypeVar with constraints incorrectly solved when `Unknown` argument is passed in

### Summary

```py
def f[T: (str, bytes)](x: T) -> T:
    return x

def g(x):
    reveal_type(f(x))  # revealed: str
```

https://play.ty.dev/dfbe3306-e4f1-46c1-a888-d8b178dc86b0

`str` feels much too confident here -- I think this should either be `Unknown` or `str | bytes`?

### Version

_No response_