fix: auto-fix code issues (cron)

- 修复缺失导入: main.py 添加 AttributeTemplate 和 EntityAttribute 导入
- 修复裸异常捕获: 将 BaseException 改为具体异常类型
  - neo4j_manager.py: Exception
  - main.py: json.JSONDecodeError, ValueError, Exception
  - export_manager.py: AttributeError, TypeError, ValueError
  - localization_manager.py: ValueError, AttributeError
  - performance_manager.py: TypeError, ValueError
  - plugin_manager.py: OSError, IOError
- 修复部分行长度问题: security_manager.py 长行拆分

backend/main.py

@@ -59,7 +59,13 @@ except ImportError:
     TINGWU_AVAILABLE = False
 
 try:
-    from db_manager import Entity, EntityMention, get_db_manager
+    from db_manager import (
+        AttributeTemplate,
+        Entity,
+        EntityAttribute,
+        EntityMention,
+        get_db_manager,
+    )
 
     DB_AVAILABLE = True
 except ImportError as e:
@@ -2016,7 +2022,7 @@ async def agent_suggest(project_id: str, _=Depends(verify_api_key)):
         try:
             data = json.loads(json_match.group())
             return data
-        except BaseException:
+        except (json.JSONDecodeError, ValueError):
             pass
 
     return {"suggestions": []}
@@ -3060,7 +3066,7 @@ async def export_report_pdf_endpoint(project_id: str, _=Depends(verify_api_key))
             reasoner = get_knowledge_reasoner()
             summary_result = reasoner.generate_project_summary(project_id, db)
             summary = summary_result.get("summary", "")
-        except BaseException:
+        except Exception:
             pass
 
     export_mgr = get_export_manager()