feat & refactor: 重构agents目录结构；AI回复模块agent结构封装

api/app/agents/chat/helpers.py

@@ -0,0 +1,49 @@
+"""聊天 Agent 共享工具：历史获取、格式化、存储"""
+from datetime import datetime
+from typing import Any, List
+
+from langchain_core.messages import AIMessage, HumanMessage
+
+from app.core.redis import redis_service
+
+
+async def get_history_messages(conversation_id: str) -> List[Any]:
+    """从 Redis 获取对话历史"""
+    history = await redis_service.get_conversation_history(conversation_id)
+    messages = []
+    for msg in history:
+        if msg["role"] == "human":
+            messages.append(HumanMessage(content=msg["content"]))
+        elif msg["role"] == "ai":
+            messages.append(AIMessage(content=msg["content"]))
+    return messages
+
+
+def format_history_string(messages: List[Any]) -> str:
+    """将消息列表格式化为 Human/Assistant 字符串"""
+    history_parts = []
+    for msg in messages:
+        if isinstance(msg, HumanMessage):
+            history_parts.append(f"Human: {msg.content}")
+        elif isinstance(msg, AIMessage):
+            history_parts.append(f"Assistant: {msg.content}")
+    return "\n\n".join(history_parts)
+
+
+async def save_message(
+    conversation_id: str,
+    role: str,
+    content: str,
+    message_type: str = "text",
+    voice_session_id: str | None = None,
+    timestamp: datetime | str | int | None = None,
+) -> None:
+    """保存消息到 Redis"""
+    await redis_service.add_message(
+        conversation_id,
+        role,
+        content,
+        message_type=message_type,
+        voice_session_id=voice_session_id,
+        timestamp=timestamp.isoformat() if isinstance(timestamp, datetime) else timestamp,
+    )