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>

NewNativeStubs/D3DService/NOTES.md

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+# D3DService.DLL
+
+## Origin
+**Entirely new** — no corresponding code in the old source tree.
+Provides a higher-level 3D graphics API that plugins can use to render 3D objects
+in the game world (meshes, 3D text, transformed geometry).
+
+## Binary Facts
+- Size: **262 KB** (the largest of the new native modules)
+- Type: COM in-process server (DLL)
+- Standard 4 COM exports: `DllCanUnloadNow`, `DllGetClassObject`, `DllRegisterServer`, `DllUnregisterServer`
+
+## Key Imports
+| DLL | Functions |
+|-----|-----------|
+| **Inject.DLL** | `BeginSceneO`, `EndSceneO` |
+| **d3dx9_30.dll** | `D3DXCreateRenderToSurface`, `D3DXLoadMeshFromXResource`, `D3DXLoadMeshFromXW`, `D3DXCreateTextW`, `D3DXMatrixTranslation`, `D3DXMatrixRotationY`, and others |
+
+## What It Does
+- Loads `.x` mesh files (from resources or from disk)
+- Creates 3D text geometry
+- Performs matrix transforms (translation, rotation)
+- Renders to off-screen surfaces
+- Essentially a "3D drawing toolkit" layered on top of Inject's scene hooks
+
+## Reconstruction Notes
+- **LOOK AT:** `Managed/Decal.Interop.D3DService/` for the COM interface definitions
+  this DLL must implement. That directory contains **8 decompiled C# files**.
+- There is **no old source** to reference. This must be reimplemented from:
+  1. The COM interfaces defined in the interop assembly
+  2. Knowledge of the D3DX9 API calls it makes
+  3. Understanding of how `BeginSceneO`/`EndSceneO` work (see `Native/Inject/`)
+- This is the most complex new module to reconstruct due to its size and the
+  lack of any prior source code.

NewNativeStubs/DHS/NOTES.md

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+# DHS.DLL (Decal Hotkey System)
+
+## Origin
+Factored out of the old **DecalInput.DLL** — the hotkey registration, detection,
+and dispatch logic was extracted into its own COM server.
+
+## Binary Facts
+- Size: **139 KB**
+- Type: COM in-process server (DLL)
+- Standard 4 COM exports: `DllCanUnloadNow`, `DllGetClassObject`, `DllRegisterServer`, `DllUnregisterServer`
+
+## What It Does
+Manages hotkey bindings for Decal plugins — registering key combinations, detecting
+when they are pressed, and firing events to the appropriate plugin. This was
+previously part of DecalInput's responsibilities.
+
+## Reconstruction Notes
+- **COMPARE WITH:** The old source files:
+  - `Native/DecalInput/Hotkey.cpp`
+  - `Native/DecalInput/Hotkey.h`
+  
+  The DHS module almost certainly started as a copy of that hotkey code, then was
+  expanded and wrapped in its own COM server.
+
+- **LOOK AT:** `Managed/Decal.Interop.DHS/` for the COM interface definitions
+  this DLL must implement. That directory contains **13 decompiled C# files**.
+
+- **Strategy:** Start by extracting the hotkey-related classes from the old
+  `DecalInput` source, then wrap them in the COM interfaces defined by the
+  interop assembly. The delta between old `Hotkey.cpp` and the new interop
+  interfaces will show what was added/changed.

NewNativeStubs/DecalRender/NOTES.md

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+# DecalRender.DLL
+
+## Origin
+Factored out of the old **Inject.DLL** — the rendering functionality (texture creation,
+font rendering, surface blitting) that previously lived inside Inject was moved into
+this dedicated COM server.
+
+## Binary Facts
+- Size: **108 KB**
+- Type: COM in-process server (DLL)
+- Standard 4 COM exports: `DllCanUnloadNow`, `DllGetClassObject`, `DllRegisterServer`, `DllUnregisterServer`
+
+## Key Imports
+| DLL | Functions |
+|-----|-----------|
+| **Inject.DLL** | `BeginSceneO`, `EndSceneO` |
+| **d3dx9_30.dll** | `D3DXCreateTexture`, `D3DXLoadSurfaceFromMemory`, `D3DXCreateFontW`, and others |
+
+## What It Does
+Provides the 2D rendering layer for Decal's overlay UI — creating textures, loading
+surfaces from memory, and drawing text with DirectX fonts. Inject.DLL hooks the
+Direct3D scene begin/end, and DecalRender plugs into those hooks to draw.
+
+## Reconstruction Notes
+- **LOOK AT:** `Managed/Decal.Interop.Render/` for the COM interface definitions
+  this DLL must implement. That directory contains **19 decompiled C# files**
+  describing every interface, enum, and coclass.
+- **LOOK AT:** The old `Native/Inject/` source for rendering code that was likely
+  moved here. Search for anything that touches `IDirect3DTexture9`, `ID3DXFont`,
+  surface blitting, etc.
+- The interop assembly will define the exact vtable layout the managed side expects.
+  Every COM interface in `Decal.Interop.Render` maps to an interface this DLL exposes.

NewNativeStubs/SpellFilter/NOTES.md

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+# SpellFilter.DLL
+
+## Origin
+**Entirely new** — no corresponding code in the old source tree.
+A dedicated module for filtering and managing spell-related game data.
+
+## Binary Facts
+- Size: **185 KB**
+- Type: COM in-process server (DLL)
+- Standard 4 COM exports: `DllCanUnloadNow`, `DllGetClassObject`, `DllRegisterServer`, `DllUnregisterServer`
+
+## What It Does
+Provides spell filtering functionality for Asheron's Call — likely parsing spell
+tables from the DAT files, categorizing spells, and letting plugins query/filter
+spells by school, level, name, or other criteria.
+
+## Reconstruction Notes
+- **LOOK AT:** `Managed/Decal.Interop.SpellFilter/` for the COM interface definitions
+  this DLL must implement. That directory contains **20 decompiled C# files** — the
+  most of any interop assembly, suggesting a rich API surface.
+
+- There is **no old source** to reference. This must be reimplemented from:
+  1. The COM interfaces defined in the interop assembly
+  2. Understanding of AC's spell data structures (from the DAT file format)
+  3. Possibly referencing `Native/DecalDat/` for how spell data was already
+     being parsed from DAT files
+  4. Possibly referencing `Native/DecalFilters/` for the general filtering
+     pattern used by Decal
+
+- The 20 interop files suggest this module exposes multiple interfaces for
+  spell tables, individual spells, spell schools, filtering criteria, etc.