Add PowerShell scripting support in Aspire AppHost

[oising]

Closes #707

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 (README.md)
  • 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

[aaronpowell]

Looks like a good start, there's some code changes I've got in there.

Can you also look at the unit tests as well as the integration tests, to match the test design of other integrations.

Also, it doesn't appear that the projects are in the slnx so they'll need to be added to ensure they are built.

Lastly, the PowerShell expects the Azure CLI to be installed, maybe we should have simpler scripts without those dependencies, otherwise the devcontainer + CI will need to be updated to ensure that the Azure CLI is installed.

[Copilot]

Pull Request Overview

This PR adds PowerShell scripting support to the Aspire AppHost by introducing new PowerShell resource types, runspace pool management, and corresponding integration tests and documentation.

• Adds a new PowerShell scripting project and supporting resource builders/extensions.
• Introduces integration tests to validate script execution and host functionality.
• Updates solution and project files to integrate with the existing Aspire framework.

Reviewed Changes

Copilot reviewed 16 out of 16 changed files in this pull request and generated 3 comments.

File	Description
tests/CommunityToolkit.Aspire.Hosting.PowerShell.Tests/*	New tests for PowerShell resource execution.
src/CommunityToolkit.Aspire.Hosting.PowerShell/*	New implementation of PowerShell scripting and runspace pool resources.
examples/powershell/*	Example app host demonstrating usage of the new PowerShell scripting support.
Directory.Packages.props	Updated package references to support PowerShell SDK.

[oising]

lgtm