Add conceptual documentation for new .NET Extensions packages

[Copilot]

• Explore repository structure and existing .NET Extensions documentation
• Research packages to be documented
• Create conceptual article for Microsoft.Extensions.DependencyInjection.AutoActivation
• Create conceptual article for Microsoft.Extensions.AsyncState
• Create conceptual article for Microsoft.Extensions.AmbientMetadata.Application
• Create conceptual article for Microsoft.Extensions.TimeProvider.Testing
• Create conceptual article for Microsoft.Extensions.AuditReports
• Update TOC to include new articles
• Validate articles for style and standards compliance
• Address feedback: Fix IAsyncState references to use non-generic interface
• Address review feedback on extracted code samples (NET 10, Task.Yield, required properties)
• Address @gewarren review comments:
  • Updated all package versions to 10.0.0 across all articles
  • Fixed IAsyncState section (removed incorrect code with non-existent .Value property)
  • Fixed best practices descriptions in async-state.md
  • Fixed Metrics/Compliance/Metadata report descriptions in audit-reports.md
  • Removed localization-problematic code comments from inline code blocks
  • Fixed :::code source paths in auto-activation.md (added ../ for new subdirectory location)
• Extract remaining inline code samples to compiled projects (ambient-metadata-application, timeprovider-testing, audit-reports)

Summary

All review feedback addressed. All package versions updated to 10.0.0. Documentation style improved per Microsoft style guide.

Original prompt

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This section details on the original issue you should resolve

<issue_title>[Epic] Docs for new .NET Extensions</issue_title>
<issue_description>The following issue serves as an Epic, capturing task (issues) for individual work, such as but not limited to, conceptualizing and reasoning about various aspects of programming for .NET with numerous NuGet packages. Each package extends workload-agnostic cloud-native primitives, and fundamental building blocks for creating resilient, diagnostic-empowered, and robust features like health-checks and dependency injection (DI) auto-activation.

Each conceptual article with be interleaved into an appropriate section (or sub-section) of the existing .NET libraries content.

Important
The following two subsets, track currently published NuGet packages, publicly available in a prerelease state. If they're not listed here, then they're not going to have a conceptual article written for them:

.NET Extensions:

• Microsoft.Extensions.Http.AutoClient
  • PR: HTTP AutoClient NuGet package content #36970 — 👀: Ctrl + 👆 for live
• Microsoft.Extensions.Resilience
  • PR: Resiliency in .NET content #37270 — 👀: Ctrl + 👆 for live
• Microsoft.Extensions.Http.Resilience
  • PR: Resiliency in .NET content #37270 — 👀: Ctrl + 👆 for live
• Microsoft.Extensions.Diagnostics.Probes
  • PR: New .NET diagnostics NuGet packages content. #37455 — 👀: Ctrl + 👆 to preview
• Microsoft.Extensions.Diagnostics.ResourceMonitoring
  • PR: New .NET diagnostics NuGet packages content. #37455 — 👀: Ctrl + 👆 to preview
• Microsoft.Extensions.Diagnostics.ExceptionSummarization
  • PR: New .NET diagnostics NuGet packages content. #37455 — 👀: Ctrl + 👆 to preview
• Microsoft.Extensions.Diagnostics.HealthChecks.Common
  • PR: New .NET diagnostics NuGet packages content. #37455 — 👀: Ctrl + 👆 to preview
• Microsoft.Extensions.Diagnostics.HealthChecks.ResourceUtilization
  • PR: New .NET diagnostics NuGet packages content. #37455 — 👀: Ctrl + 👆 to preview
• Microsoft.Extensions.DependencyInjection.AutoActivation
• Microsoft.Extensions.AsyncState
• Microsoft.Extensions.AmbientMetadata.Application
• Microsoft.Extensions.TimeProvider.Testing
• Microsoft.Extensions.AuditReports

ASP.NET Core:

I'm going to tag @Rick-Anderson here, who from the ASP.NET Docs team can write a new conceptual article for the following NuGet package?

• Microsoft.AspNetCore.HeaderParsing</issue_description>

<agent_instructions>Please continue work on this issue, the task list has links to NuGet packages that need to have corresponding conceptual content. Please start creating new articles next to the existing ones under .NET Fundamentals / Extensions. These packages are a result of the: https://github.com/dotnet/extensions repo. Use that as a source of truth.</agent_instructions>

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

Fixes #37411

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Internal previews

📄 File	🔗 Preview link
docs/core/extensions/async-state.md	Asynchronous state management
docs/core/extensions/audit-reports.md	Example GitHub Actions workflow
docs/core/extensions/dependency-injection/auto-activation.md	Dependency injection auto-activation
docs/core/extensions/file-globbing.md	File globbing in .NET
docs/core/extensions/timeprovider-testing.md	Testing with FakeTimeProvider
docs/fundamentals/toc.yml	docs/fundamentals/toc

[IEvangelist]

Hey @copilot - This looks good so far, but I'm seeing the IAsyncState<T> doesn't exist. Instead it's simply IAsyncState, please see my ssuggestions.

[IEvangelist]

@copilot please address my feedback

[Copilot]

@copilot please address my feedback

Fixed in commit 4c82751. Updated all references from IAsyncState<T> to IAsyncState throughout the async-state.md article.

[BillWagner]

@copilot

Separate the code samples that are inline in the markdown files into compiled projects. See this section of the copilot instructions for details.

This set of review comments has been addressed

[Copilot]

Pull request overview

This PR adds new conceptual documentation pages for recently introduced .NET Extensions packages and wires them into the .NET fundamentals table of contents, along with compiled snippet projects for some of the new articles.

Changes:

• Adds new conceptual articles for AsyncState, DI auto-activation, TimeProvider testing (FakeTimeProvider), and AuditReports.
• Updates docs/fundamentals/toc.yml to include the new Extensions content.
• Adds new snippet projects under docs/core/extensions/snippets/... to support the new docs.

Reviewed changes

Copilot reviewed 16 out of 16 changed files in this pull request and generated 16 comments.

Show a summary per file

File	Description
docs/fundamentals/toc.yml	Adds TOC entries for the new Extensions articles.
docs/core/extensions/timeprovider-testing.md	New conceptual article for Microsoft.Extensions.TimeProvider.Testing and FakeTimeProvider.
docs/core/extensions/audit-reports.md	New conceptual article for Microsoft.Extensions.AuditReports and MSBuild report generation.
docs/core/extensions/async-state.md	New conceptual article for Microsoft.Extensions.AsyncState.
docs/core/extensions/dependency-injection/auto-activation.md	New conceptual article for Microsoft.Extensions.DependencyInjection.AutoActivation.
docs/core/extensions/file-globbing.md	Minor formatting/link update for the FileSystemGlobbing package reference.
docs/core/extensions/snippets/dependency-injection-auto-activation/**	New compiled snippet projects for auto-activation examples.
docs/core/extensions/snippets/async-state/**	New compiled snippet projects for async state examples.

[BillWagner]

This is great. I had a number of comments around the code. Most of them are to use primary constructors: Many of these types are the primary use case for primary ctors: A type that requires one or more dependencies as part of its initialization.

Also, many of the same project files use .NET 9 instead of .NET 10 (which all the code uses). That should be consistent.

Once you've looked at the comments,