Create onnxruntime\capi before copying the OpenVINO EP on Windows

<details><summary>Claude's draft</summary>

The onnxruntime-ep-openvino prefix does not contain onnxruntime\capi, and
cmd's copy does not create missing directories (install -D does on linux),
so win-64 failed with "The system cannot find the path specified" and
"0 file(s) copied" after onnxruntime_providers_openvino.dll had linked.

Resume this Claude session:
```
cd /home/mark/git/feedstock
claude --resume fdaba65c-5a43-4f26-a32f-d49b747fdbd7
```
</details>

Claude-Session: https://claude.ai/code/session_01R9WZp6UVaiXYyC2hWTNWZY

Author: hmaarrfk

recipe/recipe.yaml

@@ -420,6 +420,7 @@ outputs:
         # which for the statically linked Python bindings is onnxruntime/capi.
         - if: win
           then:
+            - if not exist "%SP_DIR%\onnxruntime\capi" mkdir "%SP_DIR%\onnxruntime\capi"
             - copy /Y build-ov\Release\onnxruntime_providers_openvino.dll "%SP_DIR%\onnxruntime\capi\"
           else:
             - install -D -m 755 build-ov/Release/libonnxruntime_providers_openvino.so "${SP_DIR}/onnxruntime/capi/libonnxruntime_providers_openvino.so"