[cDAC]: convert DacDbi GetRcwCachedInterfacePointers to EnumerateRcwCachedInterfacePointers and implement in cDAC

[Copilot]

• Convert GetRcwCachedInterfacePointers to EnumerateRcwCachedInterfacePointers
• Create template for these add-to-list callbacks

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[Copilot]

Pull request overview

This PR converts the DAC/DBI RCW cached interface pointer query from an array-returning API to a callback-based enumeration API and adds the cDAC implementation path.

Changes:

• Replaces GetRcwCachedInterfacePointers with EnumerateRcwCachedInterfacePointers across DAC/DBI interface definitions and consumers.
• Implements cDAC RCW interface pointer enumeration using IBuiltInCOM.GetRCWInterfaces.
• Adds a reusable DI-side CallbackAccumulator<T> helper and applies it to heap segment and RCW interface pointer enumeration.

Show a summary per file

File	Description
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Legacy/Dbi/IDacDbiInterface.cs	Updates the managed DAC/DBI interface signature to the callback-based RCW enumerator.
src/native/managed/cdac/Microsoft.Diagnostics.DataContractReader.Legacy/Dbi/DacDbiImpl.cs	Adds the cDAC implementation for enumerating RCW cached interface pointers.
src/coreclr/vm/runtimecallablewrapper.h	Removes the old RCW helper that built an array of cached interface pointers.
src/coreclr/inc/dacdbi.idl	Updates the IDL contract with the new callback typedef and method.
src/coreclr/debug/inc/dacdbiinterface.h	Updates the native DAC/DBI interface declaration and comments.
src/coreclr/debug/di/rspriv.h	Adds the reusable callback accumulator helper.
src/coreclr/debug/di/process.cpp	Refactors heap segment enumeration to use CallbackAccumulator<T>.
src/coreclr/debug/di/divalue.cpp	Updates ICorDebugComObjectValue::GetCachedInterfacePointers to consume the new callback-based DAC API.
src/coreclr/debug/daccess/dacdbiimpl.h	Updates the DAC implementation declaration.
src/coreclr/debug/daccess/dacdbiimpl.cpp	Implements native callback-based RCW interface pointer enumeration.

Copilot's findings

• Files reviewed: 10/10 changed files
• Comments generated: 1

[noahfalk]

Looks nice 👍