bugfix：修复部分提示词导致的格式错误问题及langfuse客户端复用bug

app/prompt/intent.py

@@ -8,7 +8,9 @@ def build_intent_question() -> ChoiceDecision:
         # 区分意图模糊与修改细节缺失，后者交给需求理解
         instructions=(
             "Classify the user's primary intent. "
-            "Read `prompt` together with `clarification_history`; later answers clarify or correct earlier requests. "
+            "Classify the latest user answer in `clarification_history`, or `prompt` when there is no history. "
+            "Use earlier turns and the selected option to resolve references; the latest answer overrides earlier conflicting intent. "
+            "Once the requested action or response is clear, earlier ambiguity does not require another confirmation. "
             "Choose modify_screen only when the user explicitly requests an actual edit. "
             "Choose qa for clear requests for a textual answer or general conversation, including information, explanation, diagnosis, advice, and assistant identity or capabilities. "
             "Requests need not be phrased as questions; being unrelated to screens does not make an intent unclear. "
@@ -24,6 +26,6 @@ def build_intent_question() -> ChoiceDecision:
             # 明确的文字回答或交流请求，包括助手身份和能力，但没有要求实际操作大屏
             "qa": "Clearly request a textual answer or general conversation without requesting screen creation or an actual edit; includes assistant identity and capabilities, information, reasons, diagnosis, and suggestions, e.g. 这个图为什么没有数据 or 这个图怎么优化",
             # 语义上没有明确表达要问什么或做什么，不等同于模型分数低
-            "unclear": "The user's desired response or action cannot be determined from the request and clarification history, so clarification is needed to decide what to do; includes vague feedback, references, or an unspecified request to look, e.g. 这个图不太对, 这个有点问题, 帮我看看这个",
+            "unclear": "The user's desired response or action is still undetermined after incorporating the latest answer and selected option; vague feedback such as 这个图不太对 is unclear only while subsequent answers have not resolved what to do",
         },
     )