WN: Move Code snippets into working project examples - SignalR - WebSockets - ActivitySource

[wadepickett]

Related to #34183

I moved this out separately to track just my work since the original was assigned to a group but only one person can be listed on the org tracking item.

Complete the following before .NET 9 GA for What's New:

What's new PR entries where I also moved the code to projects and linked back in. For each one the code sample was created inline by the dev team and I went back and created an ASP.NET project for it with working code, tested and linked the code back in.

PR #33318
Moved the original inline code from dev for What's New .NET 9 Prev 7 for the SignalR section to a project that was compiled and tested.

PR #33460
Moved the original inline code from dev for What's New .NET 9 RC1 for WebSockets Keep-Alive Timeout to a project.

PR #34183
Recreated both SignalR ActivitySource examples for both client and server into an app project and the linked back in.

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Associated WorkItem - 350921

[wadepickett]

This issue fixed with:
#33318
#33460
#34183