[cDAC] implement GetGCHeapDetails and GetGCHeapStaticData

[max-charlamb]

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[Copilot]

Pull Request Overview

This PR implements two new cDAC methods for retrieving GC heap details: GetGCHeapDetails for server mode GC and GetGCHeapStaticData for workstation mode GC. The implementation replaces placeholder methods with full functionality that extracts comprehensive GC heap information including generation tables, finalization data, and various heap-specific pointers.

Key changes:

• Adds complete implementations for ISOSDacInterface.GetGCHeapDetails and ISOSDacInterface.GetGCHeapStaticData
• Introduces new data contracts and structures for accessing GC heap data from both workstation and server GC configurations
• Extends the GC contract with new APIs for retrieving heap bounds, GC state, and detailed heap data

Reviewed Changes

Copilot reviewed 15 out of 15 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
SOSDacImpl.cs	Implements GetGCHeapDetails and GetGCHeapStaticData with comprehensive GC heap data extraction and debug validation
ISOSDacInterface.cs	Adds GCConstants, DacpGenerationData, and DacpGcHeapDetails structures with updated method signatures
Generation.cs	New data contract for accessing GC generation information including allocation context and segment data
GCHeap.cs	New data contract for server GC heap access with comprehensive heap field mapping
CFinalize.cs	New data contract for accessing finalization queue fill pointers
GC_1.cs	Extends GC contract with heap data retrieval methods for both workstation and server modes
Constants.cs	Adds global pointer constants for GC heap field access
DataType.cs	Registers new GC-related data types
IGC.cs	Defines new heap data structures and extends IGC interface with heap access APIs
datadescriptor.inc (vm)	Adds GC address bound globals
gcpriv.h	Adds friend declaration for CFinalize cdac_data access
gc.cpp	Fixes background GC build variant flag logic
datadescriptor.inc (gc)	Comprehensive GC data structure definitions for heap, generation, and finalization data
datadescriptor.h	Adds cdac_data specializations for gc_heap and CFinalize types
GC.md	Updates documentation with new GC contract APIs and data structures