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>

Managed/Decal.Adapter/Decal.Adapter.Wrappers/ObjectClass.cs

@@ -0,0 +1,49 @@
+namespace Decal.Adapter.Wrappers;
+
+public enum ObjectClass
+{
+	Unknown,
+	MeleeWeapon,
+	Armor,
+	Clothing,
+	Jewelry,
+	Monster,
+	Food,
+	Money,
+	Misc,
+	MissileWeapon,
+	Container,
+	Gem,
+	SpellComponent,
+	Key,
+	Portal,
+	TradeNote,
+	ManaStone,
+	Plant,
+	BaseCooking,
+	BaseAlchemy,
+	BaseFletching,
+	CraftedCooking,
+	CraftedAlchemy,
+	CraftedFletching,
+	Player,
+	Vendor,
+	Door,
+	Corpse,
+	Lifestone,
+	HealingKit,
+	Lockpick,
+	WandStaffOrb,
+	Bundle,
+	Book,
+	Journal,
+	Sign,
+	Housing,
+	Npc,
+	Foci,
+	Salvage,
+	Ust,
+	Services,
+	Scroll,
+	NumObjectClasses
+}