``numpy.ctypeslib.as_ctypes`` now does not support scalar types

numpy.ctypeslib.as_ctypes now does not support scalar types

The function numpy.ctypeslib.as_ctypes has been updated to only accept numpy.ndarray. Passing a scalar type (e.g., numpy.int32(5)) will now raise a TypeError. This change was made to avoid the issue gh-30354 <https://github.com/numpy/numpy/issues/30354>__ and to enforce the readonly nature of scalar types in NumPy. The previous behavior relied on undocumented implicit temporary arrays and was not well-defined. Users who need to convert scalar types to ctypes should first convert them to an array (e.g., numpy.asarray) before passing them to numpy.ctypeslib.as_ctypes.

__array_interface__ changes on scalars

Scalars now export the __array_interface__ directly rather than including an array copy as a __ref entry. This means that scalars are now exported as read-only while they previously exported as writeable. The path via __ref was undocumented and not consistently used even within NumPy itself.