add keyword extraction time elapsed to the little lamp. (#3207)

### What problem does this PR solve?



### Type of change

- [x] Refactoring

api/db/services/dialog_service.py

@@ -196,6 +196,8 @@ def chat(dialog, messages, stream=True, **kwargs):
         questions = [full_question(dialog.tenant_id, dialog.llm_id, messages)]
     else:
         questions = questions[-1:]
+    refineQ_tm = timer()
+    keyword_tm = timer()
 
     rerank_mdl = None
     if dialog.rerank_id:
@@ -208,6 +210,7 @@ def chat(dialog, messages, stream=True, **kwargs):
     else:
         if prompt_config.get("keyword", False):
             questions[-1] += keyword_extraction(chat_mdl, questions[-1])
+            keyword_tm = timer()
 
         tenant_ids = list(set([kb.tenant_id for kb in kbs]))
         kbinfos = retr.retrieval(" ".join(questions), embd_mdl, tenant_ids, dialog.kb_ids, 1, dialog.top_n,
@@ -267,7 +270,9 @@ def chat(dialog, messages, stream=True, **kwargs):
         if answer.lower().find("invalid key") >= 0 or answer.lower().find("invalid api") >= 0:
             answer += " Please set LLM API-Key in 'User Setting -> Model Providers -> API-Key'"
         done_tm = timer()
-        prompt += "\n\n### Elapsed\n  - Retrieval: %.1f ms\n  - LLM: %.1f ms"%((retrieval_tm-st)*1000, (done_tm-st)*1000)
+        prompt += "\n\n### Elapsed\n  - Refine Question: %.1f ms\n  - Keywords: %.1f ms\n  - Retrieval: %.1f ms\n  - LLM: %.1f ms" % (
+            (refineQ_tm - st) * 1000, (keyword_tm - refineQ_tm) * 1000, (retrieval_tm - keyword_tm) * 1000,
+            (done_tm - retrieval_tm) * 1000)
         return {"answer": answer, "reference": refs, "prompt": prompt}
 
     if stream: