Added infrastructure to CODEOWNERS

[MiYanni]

Summary

As of recent, I've seen some activity around the SDK pipeline and templates. So, I wanted to add myself to the CODEOWNERS file so I'd be notified when changes occur to these files.

[Copilot]

Pull Request Overview

This PR adds the contributor to the CODEOWNERS file to receive notifications for changes to SDK pipeline and template files. The changes include documentation improvements and ownership assignments for infrastructure-related files.

• Added documentation link for CODEOWNERS syntax
• Standardized area comment formatting for consistency
• Added ownership for pipeline configuration files

[github-actions]

This PR is targeting main, which is now for .NET 11-facing work. If you intended to target .NET 10, either retarget this PR to release/10.0.1xx or make sure you backport the change to release/10.0.1xx after merging. See #50394 for more details.

[MiYanni]

/ba-r stuck

[MiYanni]

Despite using the /ba-r command, the Build Analysis still seems to be stuck. This is likely because the required check for running dotnet-sdk-public-ci was skipped as the only file being changed is CODEOWNERS, which is ignored for running that pipeline. I'm just going to bypass merge this.