Improve AI instructions and skills

[mattleibow]

This pull request makes significant improvements to the SkiaSharp contribution workflow documentation, focusing on clearer compliance requirements, more robust build and test instructions, and better separation of workflows for adding APIs and fixing bugs. It introduces stricter branch protection guidance, mandates native builds after C API changes, and updates troubleshooting steps to prevent common errors. Additionally, it adds a dedicated skill file for bug fixes and removes the old implement-issue workflow, streamlining and clarifying the process for contributors.

Branch protection and compliance:

• Added explicit branch protection instructions to .github/skills/add-api/SKILL.md and .github/skills/bug-fix/SKILL.md, requiring feature branches for both parent and submodule repositories before making any changes. [1] [2]

Build and test workflow improvements:

• Updated the add-API workflow to require building the native library after any C API changes, with platform-specific commands and mandatory passing tests before claiming completion. Troubleshooting documentation now emphasizes that EntryPointNotFoundException is caused by missing native builds. [1] [2] [3] [4] [5]

Bug fix workflow separation:

• Added a new .github/skills/bug-fix/SKILL.md file with a structured workflow for investigating, fixing, and testing bug reports, including patterns for common bug types and mandatory regression testing.
• Removed the generic .github/skills/implement-issue/SKILL.md and associated bug-fix reference files, consolidating workflows into more focused skills. [1] [2] [3]

Checklist and documentation updates:

• Updated checklists to require feature branches before starting work and clarified verification steps for both add-API and bug-fix workflows.
• Refined API documentation skill triggers for clarity and consistency.

[github-actions]

Triage Summary

Labels will be applied to indicate that the issue pertains to documentation improvements (area/Docs) and specifically affects the SkiaSharp backend (backend/SkiaSharp).

This issue is not a regression, as there are no indications of compatibility issues or performance degradation.

Additional remarks:

• The issue focuses solely on enhancing documentation and workflows in SkiaSharp without any compatibility concerns with previous versions.
• No specific operating systems or platforms were mentioned that would warrant additional relevant labels.

Detailed Summary and Actions

Summary of the triage:

• The issue focuses on improving the SkiaSharp contribution workflow documentation, including compliance requirements and build/test instructions, which falls under documentation-related improvements.
• The specific relevance to SkiaSharp indicates a need for labels related to the backend.
• No existing problems related to compatibility, performance, or reliability were identified.

Summary of the actions that will be performed:

Action	Item	Description
Apply Label	area/Docs	The issue focuses on improving documentation related to the SkiaSharp contribution workflow.
Apply Label	backend/SkiaSharp	The issue specifically addresses the SkiaSharp backend, indicating its relevance to the documentation improvements.

This entire triage process was automated by AI and mistakes may have been made. Please let us know so we can continue to improve.