Bug: Vulkan support on Windows does not work consistently

### Contact Details _No response_ ### What happened? We do have a support for vulkan in, but there are still some configurations where it does not work properly (see e.g. [here](https://github.com/mozilla-ai/llamafile/pull/924#issuecomment-4169562650) and [here](https://github.com/mozilla-ai/llamafile/pull/924#issuecomment-4178964526)). ### Version 0.10.0 ### What operating system are you seeing the problem on? Windows ### Relevant log output See [here](https://github.com/mozilla-ai/llamafile/pull/924#issuecomment-4169562650) and [here](https://github.com/mozilla-ai/llamafile/pull/924#issuecomment-4178964526).