Add XML Comments

[TheCodeTraveler]

Mirrors CommunityToolkit.Maui.Markup PR: CommunityToolkit/Maui.Markup#13

Fixes

Fixes missing XML Comments

Description

This PR adds missing XML documentation and ensures that missing XML documentation will generate a build error going forward.

Adding an .editorconfig file to the CommunityToolkit.Maui project (which inherits from the root . editorconfig), it causes the compiler to throw a build error when XML Documentation is missing.

This ensures that future PRs with new public APIs will include XML documentation.

Detailed Solution

• Adds Project-Specific .editorconfig to CommunityTooklit.Maui
  • Inherits from the root .editorconfig, by using root = false
  • Adds dotnet_diagnostic.CS1591.severity = error for only CommunityToolkit.Maui
    • Forces missing XML documentation to cause a build error
• Adds <GenerateDocumentationFile>true</GenerateDocumentationFile> to CommunityToolkit.Maui.csproj
  • Ensures XML Documentation is required by the compiler
• Adds missing XML Documentation
• Converts MultiMathExpressionConverter.shared.cs to File-Scoped Namespace
  • Required by .editorconfig
• Converts MathExpressionConverter.shared.cs to File-Scoped Namespace
  • Required by .editorconfig