Adding GetMethodTableInitializationFlags cDAC API

[rcj1]

API from discussion yesterday

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[Copilot]

Pull Request Overview

This PR adds the GetMethodTableInitializationFlags cDAC API to determine the initialization status of method tables. The implementation checks if a class is initialized or has initialization errors by examining flags in the MethodTableAuxiliaryData structure.

Key changes:

• Adds a new Flags field to MethodTableAuxiliaryData to track initialization state
• Implements two new methods (IsClassInited and IsInitError) in the RuntimeTypeSystem contract
• Updates the SOSDacInterface14 implementation to use the new cDAC contract instead of legacy implementation

Reviewed Changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
MockDescriptors.cs	Adds Flags field to MethodTableAuxiliaryData mock descriptor for testing
SOSDacImpl.cs	Implements GetMethodTableInitializationFlags using new cDAC contracts with debug validation
ISOSDacInterface.cs	Defines MethodTableInitializationFlags enum and updates method signature
MethodTableAuxiliaryData.cs	Adds Flags property to read initialization flags from memory
RuntimeTypeSystem_1.cs	Implements IsClassInited and IsInitError methods using auxiliary data flags
IRuntimeTypeSystem.cs	Adds interface declarations for the new initialization check methods
datadescriptor.inc	Maps the Flags field to the native MethodTableAuxiliaryData structure
RuntimeTypeSystem.md	Documents the new API methods and data structure changes