Add NASA NEO data pipeline assessment

[mfiroz]

Summary

This PR contains my solution for the NASA Near Earth Object data engineering exercise.

What’s included

• Python pipeline using the NASA NeoWs Browse API
• Bronze / Silver / Gold data layout
• Parquet outputs
• exact 200-object handling
• raw Bronze preservation for both neo_objects and close_approaches
• curated Silver output with required fields
• consolidated Gold aggregations
• unit tests

How to run

pip install -e ".[dev]"
export NASA_API_KEY=your_api_key_here
pytest -v
python -m nasa_neo_pipeline.cli run