Add asset_helpers.py with tests and support it in asset definitions.

[gkirchou]

When Asset or Metadata objects are created with extra dictionaries containing numpy types (e.g., np.int64, np.float64, np.ndarray), downstream JSON serialization can fail, as these types are not directly
serializable to JSON. This issue can arise when metadata is passed via TaskOutlets.

This change introduces automatic normalization of the extra metadata upon Asset and Metadata instantiation. It recursively converts numpy integer, float, boolean, array, and complex types into standard Python types (int, float, bool, list, dict) to ensure JSON serializability.

closes: #53474

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[gkirchou]

Marked this read to review to proceed the discussion - #53474 (comment)

[Lee-W]

I would love to hear @amoghrajesh and @ashb's thoughts on handling NumPy as a special case here. This should be able to resolve the issue. However, what happens if we encounter an issue with the next library? How do we decide which libraries we should support?

If we were to doing something similar, https://github.com/apache/airflow/blob/main/airflow-core/src/airflow/serialization/serialized_objects.py is probably a better place instead?

[github-actions]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed in 5 days if no further activity occurs. Thank you for your contributions.