feat: add Python script to download specific files

[hwaipy]

Summary

• Add download_file.py, a standalone Python CLI script to download a file from a URL.
• Support --output, --timeout, --retries, and --overwrite options.
• Include retry with exponential backoff and clear success/failure terminal messages.

Testing

• Basic CLI execution and argument parsing validated by running script help.
• End-to-end download test validated by downloading a small public text file and confirming local output/size.

  

[github-actions]

Coverage report

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