added __complex__ support

[aaishwarymishra]

This pull request adds support for converting mx::array objects to Python complex numbers by implementing the

Please include a description of the problem or feature this PR is addressing. If there is a corresponding issue, include the issue #.

__complex__ method. It also extends the test suite to verify this new functionality, ensuring that both real and complex arrays behave as expected when converted to complex numbers.

New feature: Python complex conversion support

• Added a __complex__ method to the mx::array Python bindings, allowing mx::array instances to be converted to Python complex numbers using the built-in complex() function.

Test improvements

• Extended the test_to_scalar test to check that complex(mx.array(...)) returns the correct complex value for real and complex arrays, and raises a ValueError for non-scalar arrays.

Checklist

Put an x in the boxes that apply.

• I have read the CONTRIBUTING document
• I have run pre-commit run --all-files to format my code / installed pre-commit prior to committing changes
• I have added tests that prove my fix is effective or that my feature works
• I have updated the necessary documentation (if needed)

Part of the data-apis/array-api-compat#452 .

[aaishwarymishra]

While working on test my linter were showing me warning that complex is not valid input for mlx array do you think we need to update mlx array arguments?

[zcbenz]

Can it be done with just return nb::handle(PyComplex_AsCComplex(to_scalar(a).ptr()))?

[zcbenz]

While working on test my linter were showing me warning that complex is not valid input for mlx array do you think we need to update mlx array arguments?

I'm open to support complex as array input.