feat:Strip code blocks in plan data. (bytedance#738)

* feat:Strip code blocks in plan data.

* feat: add repair_json_output for current_plan_content

---------

Co-authored-by: ryan-gz <ryzhangga1991@gmail.com>

Author: ryan-gz

src/graph/nodes.py

@@ -468,7 +468,7 @@ def human_feedback_node(
         # increment the plan iterations
         plan_iterations += 1
         # parse the plan
-        new_plan = json.loads(current_plan_content)
+        new_plan = json.loads(repair_json_output(current_plan_content))
         # Validate and fix plan to ensure web search requirements are met
         configurable = Configuration.from_runnable_config(config)
         new_plan = validate_and_fix_plan(new_plan, configurable.enforce_web_search)
@@ -1233,4 +1233,4 @@ async def analyst_node(
         config,
         "analyst",
         [],  # No tools - pure reasoning
-    )
+    )