Fix prompt

prompts.yaml

@@ -319,3 +319,9 @@
   "report": |-
     Here is the final answer from your managed agent '{{name}}':
     {{final_answer}}
+final_answer:
+  pre_messages: |-
+    An agent tried to answer a user query but it got stuck and failed to do so. You are tasked with providing an answer instead. Here is the agent's memory:
+  post_messages: |-
+    Based on the above, please provide an answer to the following user task:
+    {{task}}