Implement GetCurrentAppDomain for cDAC

[barosiak]

Implement GetCurrentAppDomain for cDAC

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[Copilot]

Pull request overview

Implements IXCLRDataTask.GetCurrentAppDomain for cDAC by introducing an IXCLRDataAppDomain COM interface and a managed wrapper, plus associated signature tighten-ups and a unit test.

Changes:

• Add IXCLRDataAppDomain COM interface and ClrDataAppDomain wrapper type.
• Implement ClrDataTask.GetCurrentAppDomain by reading the AppDomain global and returning a ClrDataAppDomain.
• Update several IXCLRData* signatures to use IXCLRDataAppDomain*/IXCLRDataAppDomain** instead of void*/void**, and add a test validating the new API path.

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/native/managed/cdac/tests/ClrDataTaskTests.cs	Adds coverage for GetCurrentAppDomain returning an AppDomain object.
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Legacy/SOSDacImpl.IXCLRDataProcess.cs	Updates process interface method signatures to typed IXCLRDataAppDomain*/**.
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Legacy/IXCLRData.cs	Introduces IXCLRDataAppDomain and updates related interface signatures, including GetCurrentAppDomain.
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Legacy/ClrDataTask.cs	Implements GetCurrentAppDomain using cDAC globals, with DEBUG parity assert vs legacy DAC.
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Legacy/ClrDataModule.cs	Updates module interface method signatures to typed IXCLRDataAppDomain*/**.
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Legacy/ClrDataFrame.cs	Adjusts GetAppDomain parameter annotation to clarify AppDomain type.
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Legacy/ClrDataAppDomain.cs	Adds ClrDataAppDomain COM class wrapper (currently legacy-forwarding).

[Copilot]

_target and _appDomain are assigned but never used, which will raise CS0414 and fail the build (warnings treated as errors). Either remove these fields for now, or use them (e.g., implement at least one method using _appDomain / _target) and keep the state meaningful.

Suggested change

	internal Target Target
	=> _target;
	internal TargetPointer AppDomainHandle
	=> _appDomain;

[Copilot]

using System.Diagnostics; is only referenced inside #if DEBUG. In non-Debug builds this becomes an unused using directive (CS8019) and will fail the build because the repo treats warnings as errors. Wrap the using in #if DEBUG or remove it and fully-qualify System.Diagnostics.Debug inside the #if DEBUG block.

Suggested change

	using System;
	using System.Diagnostics;
	using System;
	#if DEBUG
	using System.Diagnostics;
	#endif

[Copilot]

This file has an unused using System; directive. With TreatWarningsAsErrors=true at the repo level, CS8019 will break the build; please remove the unused using (or add a real usage if intended).

Suggested change

using System;