Fixed prompt template again

prompts.yaml

@@ -83,12 +83,8 @@ planning:
   update_plan_post_messages: |-
     Create a revised plan (high-level only, no tool call details).  You have {{remaining_steps}} steps left.  End the plan with `<end_plan>`.
 final_answer:
-  template: |-
-    Thought: I have obtained the final solution and will return it.
-    Code:
-    ```py
-    final_answer({{answer}})
-    ```<end_code>
+  pre_messages: |-
+    Your task is complete. You must now return the final answer.
 
 managed_agent:
   task: |-