DirectML Execution Provider Error: Unable to load D3D12Core.dll

**Describe the bug**
When using the prebuilt v0.5.0 DirectML ES runtime on Windows 11 using C++, it fails with the error:

```
D3D Error 887e0003: (19196@617069187) at 00007FF89073B23F - Unable to load D3D12Core.dll. Verify D3D12SDKPath is correct.
Microsoft.Direct3DSrc\D3D\module.cpp(689)\d3d12.dll!00007FF89073B263: (caller: 00007FF89073900E) LogHr(1) tid(4afc) 887E0003 The D3D12 SDK version configuration of the host exe is invalid.
Msg:[Unable to load D3D12Core.dll. Verify D3D12SDKPath is correct.]
```

I've installed the D3D12 Agility SDK runtime files under the D3D12 folder installed in my application folder. I've tried manually setting the D3D12SDKPath environment variable with no change.

**To Reproduce**
Steps to reproduce the behavior:
1. Compile application with onnxruntime-genai DirectML ES
2. Run app

**Expected behavior**
D3D12Core.dll is able to be found, and DirectML ES loads properly.

**Desktop (please complete the following information):**
- OS: Windows 11 23H2 Build 22635.4440
- Agility SDK Version: 1.614.1
- Qt 6.8 with C++ 20

**Additional context**
Add any other context about the problem here.

Start by reproducing the failure with the prebuilt v0.5.0 DirectML ES runtime on Windows 11 using the reported C++ application setup. Read the DirectML ES loading and D3D12 Agility SDK configuration entry points, then verify the application can load D3D12Core.dll without relying on an environment-variable workaround. Done means DirectML ES loads successfully in the reproduction case.

Written by the indexing model from the issue text.