[C++][Python] Add division kernel: duration / duration -> float

[randolf-scholz]

Describe the enhancement requested

Numpy allows division of timedelta64 by timedelta64 types, resulting in plain floating points (units cancel!)

import pyarrow as pa
import numpy as np

one_second_numpy = np.timedelta64(1, "s")
one_second_arrow = pa.scalar(1, pa.duration("s"))

assert one_second_numpy / one_second_numpy == 1.0  # ✔
assert one_second_arrow / one_second_arrow == 1.0  # TypeError: unsupported operand

Component(s)

Python

[js8544]

I'll add a kernel today.

[randolf-scholz]

@js8544 It seems that the current kernel implementation is broken for negative durations: #39156

[js8544]

I confirm I can reproduce this bug. Let's me see how to fix it.