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/Inject/Attic/dlldata.c

@@ -0,0 +1,38 @@
+/*********************************************************
+   DllData file -- generated by MIDL compiler 
+
+        DO NOT ALTER THIS FILE
+
+   This file is regenerated by MIDL on every IDL file compile.
+
+   To completely reconstruct this file, delete it and rerun MIDL
+   on all the IDL files in this DLL, specifying this file for the
+   /dlldata command line option
+
+*********************************************************/
+
+#define PROXY_DELEGATION
+
+#include <rpcproxy.h>
+
+#ifdef __cplusplus
+extern "C"   {
+#endif
+
+EXTERN_PROXY_FILE( Inject )
+
+
+PROXYFILE_LIST_START
+/* Start of list */
+  REFERENCE_PROXY_FILE( Inject ),
+/* End of list */
+PROXYFILE_LIST_END
+
+
+DLLDATA_ROUTINES( aProxyFileList, GET_DLL_CLSID )
+
+#ifdef __cplusplus
+}  /*extern "C" */
+#endif
+
+/* end of generated dlldata file */