Aspire 13.2

[aaronpowell]

Closes #1126

Preparing for the aspire 13.2 release.

PR Checklist

• Created a feature/dev branch in your fork (vs. submitting directly from a commit on main)
• Based off latest main branch of toolkit
• PR doesn't include merge commits (always rebase on top of our main, if needed)
• New integration
  • Docs are written
  • Added description of major feature to project description for NuGet package (4000 total character limit, so don't push entire description over that)
• Tests for the changes have been added (for bug fixes / features) (if applicable)
• Contains NO breaking changes
• Every new API (including internal ones) has full XML docs
• Code follows all style conventions

Other information

[Copilot]

Pull request overview

This PR upgrades the Aspire Community Toolkit from version 13.1.0 to 13.2.0-preview.1.26115.1, updating SDK references, package dependencies, and NuGet configuration to support the new preview release.

Changes:

• Upgraded Aspire.AppHost.Sdk from 13.1.0 to 13.2.0-preview.1.26115.1 across 60+ example and test AppHost projects
• Updated core Aspire package versions and related dependencies (ModelContextProtocol, DotNetExtensions)
• Enabled dotnet9 package source in nuget.config for preview package access

Reviewed changes

Copilot reviewed 54 out of 54 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
Directory.Build.props	Updated AspireVersion to 13.2.0-preview.1.26115.1, cleared AspirePreviewSuffix, and updated DotNetExtensionsVersion to 10.0.2
Directory.Packages.props	Updated package versions including ModelContextProtocol (0.4.0-preview.3), pinned Elasticsearch to 13.1.0 and Logging.Abstractions to 9.0.10
nuget.config	Enabled dotnet9 package source for Aspire preview packages
CommunityToolkit.Aspire.slnx	Removed Type="Classic C#" attributes and added Solution Items folder with config files
.github/agents/hosting-integration-creator.agent.md	Standardized list formatting and updated example SDK version reference
tests/CommunityToolkit.Aspire.Testing/*.csproj	Updated to Aspire.AppHost.Sdk 13.2.0-preview.1.26115.1
tests-app-hosts/Ollama.AppHost/*.csproj	Updated to Aspire.AppHost.Sdk 13.2.0-preview.1.26115.1
examples/*/**.AppHost.csproj (59 files)	Updated to Aspire.AppHost.Sdk 13.2.0-preview.1.26115.1, except Python example which uses inconsistent version