修复重构后的导入错误和缺失模块

backend/app/subgraphs/contact/__init__.py

@@ -3,13 +3,13 @@
 Contact Subgraph Module - Complete
 """
 
-from .state import (
+from app.main_graph.state import (
     ContactState,
     Contact,
     Email,
     ContactAction
 )
-from .graph import build_contact_subgraph
+from app.main_graph.graph import build_contact_subgraph
 from .nodes import (
     parse_intent,
     list_contacts,

backend/app/subgraphs/contact/api_client.py

@@ -6,7 +6,7 @@ from typing import Dict, Any, Optional, List
 from datetime import datetime
 from dataclasses import dataclass
 
-from .state import Contact, Email
+from app.main_graph.state import Contact, Email
 
 
 # ========== 模拟数据（保留作为备选）==========

backend/app/subgraphs/contact/graph.py

@@ -6,7 +6,7 @@ Contact Subgraph Builder
 
 from app.main_graph.graph import StateGraph, START, END
 
-from .state import ContactState
+from app.main_graph.state import ContactState
 from .nodes import create_contact_nodes
 
 

backend/app/subgraphs/contact/nodes.py

@@ -10,7 +10,7 @@ from datetime import datetime
 # 公共工具
 from ..common import MarkdownFormatter
 
-from .state import ContactState, ContactAction, Contact, Email
+from app.main_graph.state import ContactState, ContactAction, Contact, Email
 from .api_client import ContactAPIClient