[DiagnosticsClient] Update APIs

[mdh1418]

While adding documentation for the SupportsEventPipeUserEventsCommand APIs (dotnet/diagnostics#5656), I figured I should update all public APIs from Microsoft.Diagnostics.NETCore.Client's DiagnosticsClient class.

The intent is to merge this PR after the next Microsoft.Diagnostics.NETCore.Client release containing the SupportsEventPipeUserEventsCommand APIs.

Update: The plan is to keep SupportsEventPipeUserEventsCommand as an internal API utilized by dotnet-trace collect-linux. So this PR now just updates the documented public APIs.

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Internal previews

📄 File	🔗 Preview link
docs/core/diagnostics/microsoft-diagnostics-netcore-client.md	Microsoft.Diagnostics.NETCore.Client API

[Copilot]

Pull request overview

This PR updates the API documentation for the Microsoft.Diagnostics.NETCore.Client library, adding documentation for the new SupportsEventPipeUserEventsCommand APIs and comprehensively updating all public APIs from the DiagnosticsClient class.

Key changes:

• Documents new SupportsEventPipeUserEventsCommand methods for checking runtime IPC command support
• Adds documentation for previously undocumented API overloads (EventPipeSession, WriteDump, ApplyStartupHook, and PerfMap methods)
• Introduces documentation for new classes (EventPipeSessionConfiguration, DiagnosticsClientConnector) and enums (WriteDumpFlags, PerfMapType, ProfilerAlreadyActiveException)

[mdh1418]

It looks like the OpenPublishing.Build warning is an unrelated file not changed in this pr, and the instructions link to resolve it is broken. The unrelated file is docs/standard/commandline/migration-guide-2.0.0-beta5.md | Warning | View | gewarren | dotnet-fundamentals |   | Line 64: [Warning] Cross reference not found: 'System.CommandLine.Option.Name'.