Document .gitignore usage for Python policy packs

[joeduffy]

Adds documentation about using .gitignore to exclude unnecessary files (*.pyc, __pycache__/, venv/, .venv/) from published policy pack archives. This helps keep the .tgz package size small.

Fixes #17027

[claude]

Review Summary

This PR adds helpful documentation about using .gitignore to manage Python policy pack size. The change is clear, accurate, and follows the repository's style conventions.

Findings

Style and formatting: ✅ Passes

• Follows existing blockquote note pattern used in the file
• Proper indentation and code block formatting
• Consistent with surrounding content

Content accuracy: ✅ Passes

• Correctly describes using .gitignore to exclude files from policy pack archives
• Appropriate examples (*.pyc, pycache/, venv/, .venv/)
• Accurate explanation of the benefit (keeping package size small)

Language and clarity: ✅ Passes

• Clear and concise
• Appropriate level of technical detail
• Good placement next to the virtual environment configuration note

Technical accuracy: ✅ Passes

• The patterns shown are standard Python exclusions
• Correctly explains the effect on the published .tgz archive

Suggestions

No issues found. The documentation addition is well-written and valuable for users looking to optimize their policy pack size.

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If you'd like me to review any additional changes or have questions, feel free to mention me (@claude) in the comments.

[pulumi-bot]

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