Convert markdown to XML documentation syntax in C# emitter

[Copilot]

Implement markdown to XML doc conversion for C# documentation

Successfully implemented the missing functionality for Documentation spector scenarios. C# XML documentation doesn't support markdown syntax, so we now convert markdown to proper XML tags.

Complete Implementation:

• Understand the problem and current implementation
• Implement markdown to XML conversion in DocHelpers.cs
  • Convert **bold** → <b>bold</b>
  • Convert *italic* → <i>italic</i>
  • Convert ***bold italic*** → <b><i>bold italic</i></b>
  • Convert - bullet → <list type="bullet">...
  • Convert 1. numbered → <list type="number">...
• Update XmlDocStatement.cs to preserve XML tags (not escape them)
• Add comprehensive unit tests (16 tests, all passing)
• Add reflection-based validation in SpectorTest methods to verify documentation conversion
• Regenerate Documentation test project with proper XML
• Validate generated code has correct XML formatting
• Applied PR feedback:
  • Refactored XmlDocStatement.cs to use HashSet for allowed XML tags
  • Refactored DocHelpers.cs to use static pre-compiled regex patterns
  • Added reflection-based validation directly in each corresponding SpectorTest method for both enums and methods
  • Merged all documentation tests into single DocumentationTests.cs file

Files Changed:

1. DocHelpers.cs - Added ConvertMarkdownToXml() with static pre-compiled regex
2. XmlDocStatement.cs - Extended SkipValidTag() using HashSet for maintainability
3. DocHelpersTests.cs - 16 unit tests for conversion logic
4. DocumentationTests.cs - Merged file containing all 6 SpectorTests with validation for both enums and methods
5. BulletPointsEnum.cs - Regenerated with proper XML documentation

Test Results:

✅ All 16 DocHelpers unit tests passing
✅ All 6 SpectorTests include reflection-based validation for both method and enum documentation
✅ Build succeeds without errors
✅ Generated documentation has proper XML tags
✅ XML tags are not escaped (no < or >)

The implementation is complete and ready for review!

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Adopt Documentation spector scenarios</issue_title>
<issue_description>https://github.com/microsoft/typespec/tree/main/packages/http-specs/specs/documentation</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Adopt Documentation spector scenarios #9393

---

💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.

[pkg-pr-new]

Open in StackBlitz

npm i https://pkg.pr.new/microsoft/typespec/@typespec/http@9401

npm i https://pkg.pr.new/microsoft/typespec/@typespec/http-client@9401

npm i https://pkg.pr.new/microsoft/typespec/@typespec/http-client-csharp@9401

commit: 98a905c

[github-actions]

No changes needing a change description found.