feat: showing the lists which an image is a part of

backend/agents/list_agent.go

@@ -33,6 +33,8 @@ and extract some meaning about what the image is.
 You must call "listLists" to see which available lists are already available.
 Use "createList" only once, don't create multiple lists for one image.
 
+You can add an image to multiple lists, this is also true if you already created a list. But only add to a list if it makes sense to do so.
+
 **Tools:**
 * think: Internal reasoning/planning step.
 * listLists: Get existing lists