Add WFGY Core reasoning OS custom instructions

[onestardao]

Pull Request Checklist

• I have read and followed the CONTRIBUTING.md guidelines.
• 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.

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Description

This PR adds a reusable Copilot instructions file that exposes the WFGY Core 2.0 “reasoning OS” as a plain-text system prompt.

• File: instructions/wfgy-core-reasoning-os.instructions.md
• Scope: cross-cutting reasoning / debugging layer that can sit under any language- or framework-specific instructions.
• Behavior:
  • encourages Copilot to plan before writing or refactoring code,
  • prefers asking for missing context instead of guessing,
  • separates confident code from speculative / version-dependent code and ends with a short “Checks” section.
• The file also includes a 60-second A/B/C self-test prompt so users can quickly compare baseline vs core-enabled behavior inside Copilot Chat.

The underlying WFGY project is MIT-licensed; this instructions file is intended to be used under the same license.

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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

I haven’t run npm start in this fork yet, so the generated docs / tables are unchanged.
If you’d like the docs to be regenerated in this PR as well, I’m happy to follow your preferred process or update them in a follow-up commit.

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By submitting this pull request, I confirm that my contribution abides by the Code of Conduct and will be licensed under the MIT License.