egui internal wgsl shader emit a validation error on creation ( windows 11, Vulkan backend )

**Describe the bug**

When running an egui app that use wgpu and a vulkan backend, egui internal wgsl shaders are emitting a validation error at creation. App is running fine, and so far, it is unclear what is that operand 10 causing the issue

```
ERROR wgpu_hal::vulkan::instance: VALIDATION [VUID-VkShaderModuleCreateInfo-pCode-01377 (0x5821254b)]
Validation Error: [ VUID-VkShaderModuleCreateInfo-pCode-01377 ] Object 0: handle = 0x29de190f6f0, type = VK_OBJECT_TYPE_DEVICE; | MessageID = 0x5821254b | SPIR-V module not valid: Invalid source language operand: 10 The Vulkan spec states: pCode must point to either valid SPIR-V code, formatted and packed as described by the Khronos SPIR-V Specification or valid GLSL code which must be written to the GL_KHR_vulkan_glsl extension specification (https://vulkan.lunarg.com/doc/view/1.3.246.1/windows/1.3-extensions/vkspec.html#VUID-VkShaderModuleCreateInfo-pCode-01377)
```

**To Reproduce**
Steps to reproduce the behavior:
1. run on windows with a egui-wgpu using Vulkan

**Expected behavior**
There should be no spriv validation error

**Desktop (please complete the following information):**
- OS: Windows 11

Start by reproducing the issue in an egui-wgpu app on Windows 11 using the Vulkan backend. Inspect egui's internal WGSL shader creation path and the generated SPIR-V around the reported invalid source-language operand. Done means the shaders are created without the Vulkan validation error; the report names no file or test path, so those must be located first.

Written by the indexing model from the issue text.