feat: add d4r inference engines and Windows parity tooling

Add native K/M/RR inference engines, HIP kernels, replay and validation
harnesses, and Windows DLSS setup and runtime support. Include GPU
profiling tools, build and packaging scripts, platform integration
patches, and implementation documentation.

tools/d4r_event_wait.h

@@ -0,0 +1,16 @@
+#pragma once
+
+// Query completion rather than trusting HIP event flags to put the CPU to
+// sleep. Never treat NOT_READY as completion, including during retirement.
+template <typename Query, typename Sleep>
+int d4r_wait_event(Query query, Sleep sleep)
+{
+    constexpr int cudaNotReady = 600;
+    for (;;)
+    {
+        const int result = query();
+        if (result != cudaNotReady)
+            return result;
+        sleep();
+    }
+}