Support debug components. (#3994)

### What problem does this PR solve?

#3993

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

api/apps/conversation_app.py

@@ -95,6 +95,8 @@ def get():
             return d.get(k1, d.get(k2))
 
         for ref in conv.reference:
+            if isinstance(ref, list):
+                continue
             ref["chunks"] = [{
                 "id": get_value(ck, "chunk_id", "id"),
                 "content": get_value(ck, "content", "content_with_weight"),