change topic setup.py to packaging

[codomposer]

Description

Renamed the "setup.py" topic to "Packaging" to better reflect modern Python packaging practices and make it more accessible for Python beginners.

Fixes

Closes #364

Changes

Content Updates

• ✅ Created new docs/cheatsheet/packaging.md with expanded content
• ✅ Added comprehensive section on modern packaging with pyproject.toml
• ✅ Included example pyproject.toml configuration
• ✅ Retained traditional setup.py section for reference
• ✅ Updated title and description to reflect broader packaging scope

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🔨 Latest commit	f0e611d