Initial commit: Complete open-source Decal rebuild

All 5 phases of the open-source Decal rebuild:

Phase 1: 14 decompiled .NET projects (Interop.*, Adapter, FileService, DecalUtil)
Phase 2: 10 native DLLs rewritten as C# COM servers with matching GUIDs
  - DecalDat, DHS, SpellFilter, DecalInput, DecalNet, DecalFilters
  - Decal.Core, DecalControls, DecalRender, D3DService
Phase 3: C++ shims for Inject.DLL (D3D9 hooking) and LauncherHook.DLL
Phase 4: DenAgent WinForms tray application
Phase 5: WiX installer and build script

25 C# projects building with 0 errors.
Native C++ projects require VS 2022 + Windows SDK (x86).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Native/DecalNet/MessageRoot.h

@@ -0,0 +1,90 @@
+// MessageRoot.h : Declaration of the cMessageRoot
+
+#ifndef __MESSAGEROOT_H_
+#define __MESSAGEROOT_H_
+
+#include "resource.h"       // main symbols
+
+#include "MessageImpl.h"
+
+/////////////////////////////////////////////////////////////////////////////
+// cMessageRoot
+class ATL_NO_VTABLE cMessageRoot : 
+	public CComObjectRootEx<CComSingleThreadModel>,
+	public CComCoClass<cMessageRoot, &CLSID_MessageRoot>,
+   public IMessageIteratorImpl< cMessageRoot >
+{
+public:
+	cMessageRoot()
+	{
+	}
+
+   cMessage *m_pSource;
+
+   cMessage *getSource()
+   {
+      return m_pSource;
+   }
+
+   DWORD getStartIndex()
+   {
+      return 0;
+   }
+
+   DWORD getEndIndex()
+   {
+      return m_pSource->m_fields.size();
+   }
+
+   DWORD getNextIndex()
+   {
+      if( m_nIndex != -1 )
+         return getNextIndex( m_dwIterator );
+
+      DWORD dwIterator = getStartIndex();
+
+      while( dwIterator == m_pSource->m_fields.size() )
+      {
+         if( !m_pSource->loadNextElement() )
+            return eEndIndex;
+      }
+
+      return dwIterator;
+   }
+
+   DWORD getNextIndex( DWORD dwIndex )
+   {
+      // Calculate the next index
+      DWORD dwNextIndex = dwIndex + ( m_pSource->m_fields.begin() + dwIndex )->m_nOwns;
+
+      // Insert this loop to make sure the cracking is done far enough ahead
+      // This is a loop because it's entirely possible that loading a message element
+      // will produce no fields (it's a rule that dosen't apply)
+      while( dwNextIndex == m_pSource->m_fields.size() )
+      {
+         if( !m_pSource->loadNextElement() )
+            return eEndIndex;
+      }
+
+      return dwNextIndex;
+   }
+
+   void init( cMessage *pSource )
+   {
+      m_pSource = pSource;
+      IMessageIteratorImpl< cMessageRoot >::init();
+   }
+
+DECLARE_REGISTRY_RESOURCEID(IDR_MESSAGEROOT)
+
+DECLARE_PROTECT_FINAL_CONSTRUCT()
+
+BEGIN_COM_MAP(cMessageRoot)
+	COM_INTERFACE_ENTRY(IMessageIterator)
+	COM_INTERFACE_ENTRY(IDispatch)
+END_COM_MAP()
+
+public:
+};
+
+#endif //__MESSAGEROOT_H_