Create System.Diagnostic.Activities for early data collection

This will enable Aspire to report telemetry for us prior to our own telemetry being lit up.

We'll want to

* [ ] create an ActivitySource for the Microsoft.Dotnet.Installer library
* [ ] create an Activity for the `DotnetInstaller.Install` method, adding `tags` for
   * install root
   * install arch
   * component
   * version
* [ ] Have sub-activity for the prepare and commit stages