docs(ui): add comments to nsfw & watermarker helpers

Author: psychedelicious

invokeai/frontend/web/src/features/nodes/util/graph/generation/addNSFWChecker.ts

@@ -20,6 +20,7 @@ export const addNSFWChecker = (
     use_cache: false,
   });
 
+  // The NSFW checker node is the new image output - make the previous one intermediate
   imageOutput.is_intermediate = true;
   imageOutput.use_cache = true;
   imageOutput.board = undefined;

invokeai/frontend/web/src/features/nodes/util/graph/generation/addWatermarker.ts

@@ -20,6 +20,7 @@ export const addWatermarker = (
     use_cache: false,
   });
 
+  // The watermarker node is the new image output - make the previous one intermediate
   imageOutput.is_intermediate = true;
   imageOutput.use_cache = true;
   imageOutput.board = undefined;