Use `numpy.typing` instead of `numpy.ndarray`

[paddyroddy]

Is Your Feature Request Related to a Problem? Please Describe

This allows greater control of the type of a specific NumPy array https://numpy.org/doc/stable/reference/typing.html

Describe the Solution You'd Like

No response

Describe Alternatives You've Considered

No response

Additional Context

No response

[ntessore]

Yeah, good idea. Most of the typing in this code is non-functional, but it would be great to get it to pass MyPy and PyRight. This could be very helpful in spotting bugs when we implement the generic API.