Hosting integration for Zitadel

[dealloc]

**Closes #1015 **

This PR is a continuation of the previous PR for Zitadel support: #1021

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

[aaronpowell]

I'm seeing failures in the test log starting here: https://github.com/CommunityToolkit/Aspire/actions/runs/21052154522/job/60540747581?pr=1100#step:6:497

The tests themselves don't seem to report failing, so possibly the Assert isn't capturing the stack properly.

Do the test pass locally?

[dealloc]

@aaronpowell the problem seems to happen when GetEnvironmentVariablesAsync is called and the tests just 'hang'