removed hard coded shader start up

config/runtime-host.json

@@ -24,7 +24,7 @@
   },
   "previewEnabled": true,
   "previewFps": 59.94,
-  "runtimeShaderId": "happy-accident",
+  "runtimeShaderId": "",
   "serverPort": 8080,
   "shaderLibrary": "shaders"
 }

config/runtime-host.schema.json

@@ -70,8 +70,8 @@
     },
     "runtimeShaderId": {
       "type": "string",
-      "default": "happy-accident",
-      "description": "Startup shader package id used when no saved runtime layer stack is restored."
+      "default": "",
+      "description": "Optional startup shader package id used only when no saved runtime layer stack is restored. Leave empty to keep the simple fallback renderer until layers are added or restored."
     }
   },
   "required": [