Add a pass-through renderer plugin

t5deRenderEngine.dll implements IMVU Classic's renderer plugin interface by wrapping IMVU's own OpenGL renderer, and logs what each frame calls, to prove our declarations of the interface. Built with CMake presets for 32-bit MSVC; docs/interface.md has the findings.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

CMakePresets.json

@@ -0,0 +1,44 @@
+{
+  "version": 6,
+  "cmakeMinimumRequired": { "major": 3, "minor": 28, "patch": 0 },
+  "configurePresets": [
+    {
+      "name": "windows-x86",
+      "displayName": "Windows, 32-bit (Visual Studio Build Tools)",
+      "description": "IMVU Classic is a 32-bit Visual C++ program: build for Win32 with MSVC.",
+      "generator": "Visual Studio 18 2026",
+      "architecture": { "value": "Win32", "strategy": "set" },
+      "binaryDir": "${sourceDir}/build/${presetName}",
+      "installDir": "${sourceDir}/build/${presetName}/install",
+      "condition": { "type": "equals", "lhs": "${hostSystemName}", "rhs": "Windows" }
+    }
+  ],
+  "buildPresets": [
+    { "name": "debug", "configurePreset": "windows-x86", "configuration": "Debug" },
+    { "name": "release", "configurePreset": "windows-x86", "configuration": "Release" }
+  ],
+  "testPresets": [
+    {
+      "name": "debug",
+      "configurePreset": "windows-x86",
+      "configuration": "Debug",
+      "output": { "outputOnFailure": true }
+    },
+    {
+      "name": "release",
+      "configurePreset": "windows-x86",
+      "configuration": "Release",
+      "output": { "outputOnFailure": true }
+    }
+  ],
+  "workflowPresets": [
+    {
+      "name": "release",
+      "steps": [
+        { "type": "configure", "name": "windows-x86" },
+        { "type": "build", "name": "release" },
+        { "type": "test", "name": "release" }
+      ]
+    }
+  ]
+}