Fix _as_numpy_array: use variable obj instead of string literal "obj"

[quick123-666]

Describe your changes

Fixes a bug in _as_numpy_array where hasattr was called with the string literal "obj" instead of the variable obj for the __array_interface__ check.

# Before (bug):
elif hasattr(obj, "__array__") or hasattr("obj", "__array_interface__"):
# After (fix):
elif hasattr(obj, "__array__") or hasattr(obj, "__array_interface__"):

This meant any object implementing __array_interface__ without also implementing __array__ would not be recognized as a numpy-like array by _as_numpy_array, causing it to fall through to ApproxSequenceLike instead of ApproxNumpy. In practice this could affect users with custom array types or libraries that only implement __array_interface__.

GitHub Issue Link

• Closes _as_numpy_array: hasattr uses string literal 'obj' instead of variable #14456

Testing Plan

• Added test_numpy_array_via_interface_protocol which creates a class implementing __array_interface__ without __array__ and verifies it works with approx()
• Existing test_numpy_array_implicit_conversion and test_numpy_array_protocol continue to pass (they test __array__ path)

[RonnyPfannschmidt]

closing due to ai abuse