refine components retrieval and rewrite (#2818)

### What problem does this PR solve?


### Type of change

- [x] Performance Improvement

agent/component/retrieval.py

     component_name = "Retrieval"
 
     def _run(self, history, **kwargs):
-        query = []
-        for role, cnt in history[::-1][:self._param.message_history_window_size]:
-            if role != "user":continue
-            query.append(cnt)
-        # query = "\n".join(query)
-        query = query[0]
+        # query = []
+        # for role, cnt in history[::-1][:self._param.message_history_window_size]:
+        #     if role != "user":continue
+        #     query.append(cnt)
+        # # query = "\n".join(query)
+        # query = query[0]
+        query = self.get_input()
+        query = str(query["content"][0]) if "content" in query else ""
+
         kbs = KnowledgebaseService.get_by_ids(self._param.kb_ids)
         if not kbs:
             raise ValueError("Can't find knowledgebases by {}".format(self._param.kb_ids))

agent/component/rewrite.py

             raise Exception("Sorry! Nothing relevant found.")
         self._loop += 1
 
-        conv = self._canvas.get_history(4)
+        hist = self._canvas.get_history(4)
+        conv = []
+        for m in hist:
+            if m["role"] not in ["user", "assistant"]: continue
+            conv.append("{}: {}".format(m["role"].upper(), m["content"]))
         conv = "\n".join(conv)
 
         chat_mdl = LLMBundle(self._canvas.get_tenant_id(), LLMType.CHAT, self._param.llm_id)