port(EterLib): Mutex/Thread/FileLoaderThread/GrpVertexBufferDynamic verbatim over Win32Crt kernel-object shims

Adds CreateSemaphore/ReleaseSemaphore/WaitForSingleObject/CloseHandle/
SetThreadPriority/_beginthreadex to Win32Crt; port.file_loader_thread covers
the shims, CThread and both the un-Created (40250 live) and Created loader.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

audit/port-map/EterLib/GrpVertexBufferDynamic.cpp.json

@@ -0,0 +1,29 @@
+{
+  "reference": "EterLib/GrpVertexBufferDynamic.cpp",
+  "reference_sha256": "8bffcb4a24733a2ee4312bf45a690a1f0b46c6290e17867b763f4799055f3d3c",
+  "priority": "P4",
+  "contracts": [],
+  "functions": {
+    "CDynamicVertexBuffer::Create": {
+      "status": "PORTED",
+      "impl": [
+        "src/platform/EterLib/GrpVertexBufferDynamic.cpp:CDynamicVertexBuffer::Create"
+      ],
+      "note": "Verbatim 40250. No 40250 code instantiates CDynamicVertexBuffer."
+    },
+    "CDynamicVertexBuffer::CDynamicVertexBuffer": {
+      "status": "PORTED",
+      "impl": [
+        "src/platform/EterLib/GrpVertexBufferDynamic.cpp:CDynamicVertexBuffer::CDynamicVertexBuffer"
+      ],
+      "note": "Verbatim 40250. No 40250 code instantiates CDynamicVertexBuffer."
+    },
+    "CDynamicVertexBuffer::~CDynamicVertexBuffer": {
+      "status": "PORTED",
+      "impl": [
+        "src/platform/EterLib/GrpVertexBufferDynamic.cpp:CDynamicVertexBuffer::~CDynamicVertexBuffer"
+      ],
+      "note": "Verbatim 40250. No 40250 code instantiates CDynamicVertexBuffer."
+    }
+  }
+}