chore: finalize backend feature scope

app/agents/patient_agent.py

@@ -1,6 +1,6 @@
 from collections.abc import AsyncIterator
 
-from app.agents.llm_adapter import DeepSeekClient, LLMResponse, LLMStreamChunk
+from app.agents.llm_adapter import DeepSeekClient, LLMStreamChunk
 from app.core.config import settings
 from app.models.source_case import CaseBase
 
@@ -11,23 +11,6 @@ class PatientAgent:
     def __init__(self, llm: DeepSeekClient | None = None) -> None:
         self.llm = llm or DeepSeekClient()
 
-    async def reply(
-        self,
-        case: CaseBase,
-        memory_messages: list[dict],
-        user_message: str,
-        mode: str,
-        patient_config: dict | None = None,
-    ) -> LLMResponse:
-        """问诊回复：拼接病例上下文、短期记忆和用户输入后调用 Patient Agent。"""
-        messages = self._build_messages(case, memory_messages, user_message, mode, patient_config)
-        return await self.llm.chat(
-            messages,
-            settings.llm_fast_model,
-            thinking_enabled=settings.llm_fast_thinking_enabled,
-            max_tokens=settings.llm_fast_max_tokens,
-        )
-
     async def stream_reply(
         self,
         case: CaseBase,
@@ -58,11 +41,7 @@ class PatientAgent:
         profile = case.ai_patient_profile or {}
         hidden_info = case.hidden_patient_info or {}
         config_rule = self._build_patient_config_rule(patient_config)
-        mode_rule = {
-            "novice": "新手模式：回答清楚，必要时可提示医生继续追问症状、既往史或检查。",
-            "practice": "练习模式：只回答被问到的信息，不主动给诊断建议。",
-            "teaching": "教学模式：保持患者身份，允许在回答后补充简短学习提示。",
-        }.get(mode, "只回答被问到的信息。")
+        mode_rule = "练习模式：只回答被问到的信息，不主动给诊断建议。"
         system = f"""
 你是一名标准化 AI 病人或患儿家属，只能基于病例资料回答。
 病例主诉：{case.chief_complaint}