feat: 完善词典子图，添加API调用和前端格式化工具

- 完善词典子图：添加生词本功能
- 创建API调用工具：dictionary_api
- 添加前端格式化展示工具：result_formatter.py
- 创建通讯录和资讯子图的基本结构
- 更新主图状态结构，添加MainGraphState
- 添加subgraph_builder.py用于子图集成

backend/app/graph/subgraph_builder.py

@@ -0,0 +1,157 @@
+"""
+子图整合主图构建器
+Subgraph Integration Main Graph Builder
+"""
+
+from langgraph.graph import StateGraph, START, END
+from typing import Dict, Any
+
+from .state import MainGraphState, CurrentAction
+from ..agent_subgraphs.contact import build_contact_subgraph
+from ..agent_subgraphs.dictionary import build_dictionary_subgraph
+from ..agent_subgraphs.news_analysis import build_news_analysis_subgraph
+
+
+def parse_user_intent(state: MainGraphState) -> MainGraphState:
+    """
+    解析用户意图节点
+    
+    确定该路由到哪个子图
+    """
+    state.current_phase = "intent_parsing"
+    
+    # 从messages中提取用户查询（如果user_query为空）
+    if not state.user_query and state.messages:
+        # 获取最后一条消息的内容
+        last_msg = state.messages[-1]
+        state.user_query = last_msg.content
+    
+    query_lower = state.user_query.lower()
+    
+    # 简单的关键词匹配
+    if any(keyword in query_lower for keyword in ["通讯录", "联系人", "contact", "email"]):
+        state.current_action = CurrentAction.CONTACT
+        state.intent_confidence = 0.9
+    
+    elif any(keyword in query_lower for keyword in ["词典", "单词", "翻译", "dictionary", "translate"]):
+        state.current_action = CurrentAction.DICTIONARY
+        state.intent_confidence = 0.9
+    
+    elif any(keyword in query_lower for keyword in ["资讯", "新闻", "分析", "news", "report"]):
+        state.current_action = CurrentAction.NEWS_ANALYSIS
+        state.intent_confidence = 0.9
+    
+    else:
+        # 默认是普通聊天
+        state.current_action = CurrentAction.GENERAL_CHAT
+        state.intent_confidence = 0.8
+    
+    return state
+
+
+def route_to_subgraph(state: MainGraphState) -> str:
+    """
+    条件路由：决定路由到哪个子图
+    """
+    if state.current_action == CurrentAction.NONE:
+        return "general_chat"
+    elif state.current_action == CurrentAction.GENERAL_CHAT:
+        return "general_chat"
+    elif state.current_action == CurrentAction.CONTACT:
+        return "contact_subgraph"
+    elif state.current_action == CurrentAction.DICTIONARY:
+        return "dictionary_subgraph"
+    elif state.current_action == CurrentAction.NEWS_ANALYSIS:
+        return "news_analysis_subgraph"
+    else:
+        return "general_chat"
+
+
+def general_chat_node(state: MainGraphState) -> MainGraphState:
+    """
+    普通聊天节点
+    （目前是占位符，后续整合旧的LLM调用逻辑）
+    """
+    state.current_phase = "general_chat"
+    state.final_result = f"普通聊天模式：{state.user_query}"
+    state.success = True
+    return state
+
+
+def integrate_results(state: MainGraphState) -> MainGraphState:
+    """
+    整合子图结果节点
+    """
+    state.current_phase = "integrating"
+    
+    # 整合通讯录子图结果
+    if state.contact_result:
+        state.final_result = state.contact_result.get("final_result", "")
+    
+    # 整合词典子图结果
+    elif state.dictionary_result:
+        state.final_result = state.dictionary_result.get("final_result", "")
+    
+    # 整合资讯子图结果
+    elif state.news_result:
+        state.final_result = state.news_result.get("final_result", "")
+    
+    else:
+        # 没有子图结果
+        if not state.final_result:
+            state.final_result = "处理完成"
+    
+    state.current_phase = "done"
+    return state
+
+
+def build_main_graph() -> StateGraph:
+    """
+    构建整合了子图的主图
+    
+    Returns:
+        配置好的 StateGraph
+    """
+    # 创建图
+    graph = StateGraph(MainGraphState)
+    
+    # 添加节点
+    graph.add_node("parse_intent", parse_user_intent)
+    graph.add_node("general_chat", general_chat_node)
+    graph.add_node("integrate_results", integrate_results)
+    
+    # 添加子图节点
+    contact_graph = build_contact_subgraph()
+    dictionary_graph = build_dictionary_subgraph()
+    news_analysis_graph = build_news_analysis_subgraph()
+    
+    graph.add_node("contact_subgraph", contact_graph.compile())
+    graph.add_node("dictionary_subgraph", dictionary_graph.compile())
+    graph.add_node("news_analysis_subgraph", news_analysis_graph.compile())
+    
+    # 添加边
+    # 从START开始
+    graph.add_edge(START, "parse_intent")
+    
+    # 从parse_intent根据条件路由
+    graph.add_conditional_edges(
+        "parse_intent",
+        route_to_subgraph,
+        {
+            "general_chat": "general_chat",
+            "contact_subgraph": "contact_subgraph",
+            "dictionary_subgraph": "dictionary_subgraph",
+            "news_analysis_subgraph": "news_analysis_subgraph",
+        }
+    )
+    
+    # 从普通聊天和子图到结果整合
+    graph.add_edge("general_chat", "integrate_results")
+    graph.add_edge("contact_subgraph", "integrate_results")
+    graph.add_edge("dictionary_subgraph", "integrate_results")
+    graph.add_edge("news_analysis_subgraph", "integrate_results")
+    
+    # 最终到END
+    graph.add_edge("integrate_results", END)
+    
+    return graph