Add new skill: Python PyPI Package Builder

[Dhruvpatel004]

• Created SKILL.md defining decision-driven workflow for building, testing, versioning, and publishing Python packages.
• Added reference modules covering PyPA packaging, architecture patterns, CI/CD, testing, versioning strategy, and release governance.
• Implemented scaffold script to generate complete project structure with pyproject.toml, CI workflows, tests, and configuration.
• Included support for multiple build backends (setuptools_scm, hatchling, flit, poetry) with clear decision rules.
• Added secure release practices including tag-based versioning, branch protection, and OIDC Trusted Publishing.

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Pull Request Checklist

• I have read and followed the [CONTRIBUTING.md](https://github.com/github/awesome-copilot/blob/main/CONTRIBUTING.md) guidelines.
• I have read and followed the [Guidance for submissions involving paid services](Guidance for submissions involving paid services #968).
• My contribution adds a new instruction, prompt, agent, skill, or workflow file in the correct directory.
• The file follows the required naming convention.
• The content is clearly structured and follows the example format.
• I have tested my instructions, prompt, agent, skill, or workflow with GitHub Copilot.
• I have run npm start and verified that README.md is up to date.
• I am targeting the staged branch for this pull request.

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Description

Adds the python-pypi-package-builder Skill, a comprehensive workflow for creating production-grade Python packages using modern PyPA standards.

This contribution introduces a structured, decision-driven system that helps GitHub Copilot:

• Select appropriate project structure (src/ vs flat layout)
• Choose the correct build backend based on project needs
• Apply proper versioning strategies (PEP 440 + Semantic Versioning)
• Set up linting (Ruff), type checking (mypy), and testing (pytest)
• Configure CI/CD pipelines using GitHub Actions
• Enforce secure and controlled release workflows using tag-based versioning and OIDC Trusted Publishing

It also includes a scaffold script to generate a fully functional, PyPI-ready project with best practices applied by default.

This skill addresses a real gap in Python packaging workflows, especially around consistency, automation, and release governance.

Usage examples:

• "Create a production-ready Python package with PyPA standards"
• "Set up a PyPI package with CI/CD and versioning"
• "Generate a Python SDK with proper packaging and release workflow"

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Type of Contribution

• New instruction file.
• New prompt file.
• New agent file.
• New plugin.
• New skill file.
• New agentic workflow.
• Update to existing instruction, prompt, agent, plugin, skill, or workflow.
• Other (please specify):

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Additional Notes

• The skill is modular and includes structured reference files for deeper technical guidance.
• Focuses on advanced packaging workflows beyond default Copilot capabilities.
• No external plugins or unsafe configurations are included.
• Designed to be reusable across multiple Python project types (libraries, SDKs, CLI tools, plugins).

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By submitting this pull request, I confirm that my contribution abides by the [Code of Conduct](../CODE_OF_CONDUCT.md) and will be licensed under the MIT License.

[github-actions]

🔍 Skill Validator Results

2 resource(s) checked | ✅ All checks passed

Full output

Found 1 skill(s)
[python-pypi-package-builder] 📊 python-pypi-package-builder: 4,857 BPE tokens [chars/4: 4,610] (standard ~), 38 sections, 13 code blocks
[python-pypi-package-builder]    ⚠  Skill is 4,857 BPE tokens (chars/4 estimate: 4,610) — approaching "comprehensive" range where gains diminish.
�[32m✅ All checks passed (1 skill(s))�[0m