Add DataFrame.to_array_object and Column.to_array_object

[MarcoGorelli]

Trying to move this forwards, according to my understanding

Sorry if I've misunderstood the

    While numpy arrays are not yet array-API-compliant, implementations
   may choose to return a numpy array (for numpy prior to 2.0), with the
   understanding that consuming libraries would then use the
   ``array-api-compat`` package to convert it to a Standard-compliant array.

part

[MarcoGorelli]

thanks for your review! merging then as there haven't been objections

[rgommers]

I had a post-hoc look - this LGTM, thanks both!