Add Webgpu backend (#2132)

* WebGPU first draft (shaderc bin version 8)

* WebGPU scripts

bindings/cs/bgfx.cs

@@ -1371,6 +1371,11 @@ public static partial class bgfx
 		/// </summary>
 		Vulkan,
 	
+		/// <summary>
+		/// WebGPU
+		/// </summary>
+		WebGPU,
+	
 		Count
 	}
 	

bindings/d/types.d

@@ -435,6 +435,7 @@ enum bgfx_renderer_type_t
 	BGFX_RENDERER_TYPE_OPENGLES, /// OpenGL ES 2.0+
 	BGFX_RENDERER_TYPE_OPENGL, /// OpenGL 2.1+
 	BGFX_RENDERER_TYPE_VULKAN, /// Vulkan
+	BGFX_RENDERER_TYPE_WEBGPU, /// WebGPU
 
 	BGFX_RENDERER_TYPE_COUNT
 }