Added new shaders

shaders/black-and-white/shader.json

@@ -2,7 +2,7 @@
   "id": "black-and-white",
   "name": "Black and White",
   "description": "A minimal monochrome shader that converts the decoded video input to grayscale.",
-  "category": "Built-in",
+  "category": "Color",
   "entryPoint": "shadeVideo",
   "parameters": []
 }