Add quality infrastructure: analyzers, linters, documentation, and dependency management

[Copilot]

Quality Enhancements Plan

• Add configuration files
  • Add .editorconfig for code style enforcement
  • Add .gitattributes for line ending consistency
  • Add .cspell.json for spell checking
  • Add .markdownlint.json for markdown linting
  • Add dependabot.yml for automated dependency updates
• Add documentation files
  • Add ARCHITECTURE.md
  • Add CODE_OF_CONDUCT.md
  • Add CONTRIBUTING.md
  • Add SECURITY.md
  • Enhance README.md with more details
  • Enhance AGENTS.md with more guidelines
• Update build workflow
  • Add Quality Checks job to build_on_push.yaml
  • Install and configure cspell
  • Install and configure markdownlint-cli
• Update csproj files
  • Add Microsoft.CodeAnalysis.NetAnalyzers to library project
  • Add Microsoft.CodeAnalysis.NetAnalyzers to test project
  • Add SonarAnalyzer.CSharp to both projects
  • Enable code style enforcement
• Apply code formatting
  • Fix file encoding issues
  • Add final newlines to all files
• Address PR feedback
  • Make documentation less specific to allow for future additions
  • Remove "by design" language about dependencies
  • Indicate potential for additional formats beyond TRX
  • Remove CHANGELOG.md (changelog is part of release process)
  • Add dependabot configuration for weekly dependency updates
  • Add SonarAnalyzer.CSharp for additional code quality analysis
  • Remove emphasis on zero-dependency aspect from README
  • Extract TRX namespace URI to a constant
• Run validation
  • Verify build succeeds
  • Verify tests pass
  • Verify quality checks pass
  • Verify formatting is correct
  • Address code review feedback
  • Pass security scanning

Original prompt

Please add .editorconfig, .cspell.json, and .markdownlint.json files, and enforce spelling and markdown linting in a new Quality Checks job in the build_on_push.yaml workflow.

Please add ARCHITECTURE.md, CODE_OF_CONDUCT.md, and CONTRIBUTING.md files.

Please enhance the README.md and AGENTS.md files.

Please add Microsoft.CodeAnalysis.NetAnalyzers and enable code style enforcement to the csproj files.

Consider other quality enhancements to the project.

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[Malcolmnixon]

Please do not write a CHANGELOG.md file, as the change-log is part of the release.

Please add a dependabot config file to update dependencies once a week.

Please add the SonarAnalyzer.CSharp dependency to the project, and update the associated documentation for static analysis and code quality.

[Copilot]

Please do not write a CHANGELOG.md file, as the change-log is part of the release.

Please add a dependabot config file to update dependencies once a week.
...

Done in commit 7490cd6:

1. Removed CHANGELOG.md - The file has been deleted since the changelog is managed as part of the release process.

2. Added Dependabot configuration (.github/dependabot.yml) - Configured to update NuGet and GitHub Actions dependencies weekly on Mondays, with grouping for related packages (analyzers, test dependencies).

3. Added SonarAnalyzer.CSharp (v10.4.0.108396) to both projects with proper PrivateAssets configuration. Updated documentation in AGENTS.md and ARCHITECTURE.md to reflect the addition. Suppressed false positive S1075 warnings for XML namespace URIs in test files.