Expose WinUI SwapChainPanel as a surface source type

[leksiso]

wgpu added support for WinUI SwapChainPanels in gfx-rs/wgpu#4191.

This PR makes the feature usable through wgpu-native.

Example usage:

  WGPUSurfaceSourceSwapChainPanel surfaceSource = {
      .chain = {.sType = (WGPUSType)WGPUSType_SurfaceSourceSwapChainPanel },
      .panelNative = swapChainPanel().as<ISwapChainPanelNative>().get()
  };

  WGPUSurfaceDescriptor surfaceDescriptor = {
      .nextInChain = &surfaceSource.chain,
  };

  WGPUSurface surface = wgpuInstanceCreateSurface(instance, &surfaceDescriptor);

[almarklein]

CI does not agree 😉

[leksiso]

CI does not agree 😉

Fair enough. It should agree now

[almarklein]

Thanks!