fix: auto-fix code issues (cron)

- 修复重复导入/字段
- 修复异常处理
- 修复PEP8格式问题
- 添加类型注解

backend/test_multimodal.py

@@ -42,7 +42,7 @@ except ImportError as e:
 print("\n2. 测试模块初始化...")
 
 try:
-    processor  = get_multimodal_processor()
+    processor = get_multimodal_processor()
     print("   ✓ MultimodalProcessor 初始化成功")
     print(f"     - 临时目录: {processor.temp_dir}")
     print(f"     - 帧提取间隔: {processor.frame_interval}秒")
@@ -50,14 +50,14 @@ except Exception as e:
     print(f"   ✗ MultimodalProcessor 初始化失败: {e}")
 
 try:
-    img_processor  = get_image_processor()
+    img_processor = get_image_processor()
     print("   ✓ ImageProcessor 初始化成功")
     print(f"     - 临时目录: {img_processor.temp_dir}")
 except Exception as e:
     print(f"   ✗ ImageProcessor 初始化失败: {e}")
 
 try:
-    linker  = get_multimodal_entity_linker()
+    linker = get_multimodal_entity_linker()
     print("   ✓ MultimodalEntityLinker 初始化成功")
     print(f"     - 相似度阈值: {linker.similarity_threshold}")
 except Exception as e:
@@ -67,20 +67,20 @@ except Exception as e:
 print("\n3. 测试实体关联功能...")
 
 try:
-    linker  = get_multimodal_entity_linker()
+    linker = get_multimodal_entity_linker()
 
     # 测试字符串相似度
-    sim  = linker.calculate_string_similarity("Project Alpha", "Project Alpha")
+    sim = linker.calculate_string_similarity("Project Alpha", "Project Alpha")
     assert sim == 1.0, "完全匹配应该返回1.0"
     print(f"   ✓ 字符串相似度计算正常 (完全匹配: {sim})")
 
-    sim  = linker.calculate_string_similarity("K8s", "Kubernetes")
+    sim = linker.calculate_string_similarity("K8s", "Kubernetes")
     print(f"   ✓ 字符串相似度计算正常 (不同字符串: {sim:.2f})")
 
     # 测试实体相似度
-    entity1  = {"name": "Project Alpha", "type": "PROJECT", "definition": "核心项目"}
-    entity2  = {"name": "Project Alpha", "type": "PROJECT", "definition": "主要项目"}
-    sim, match_type  = linker.calculate_entity_similarity(entity1, entity2)
+    entity1 = {"name": "Project Alpha", "type": "PROJECT", "definition": "核心项目"}
+    entity2 = {"name": "Project Alpha", "type": "PROJECT", "definition": "主要项目"}
+    sim, match_type = linker.calculate_entity_similarity(entity1, entity2)
     print(f"   ✓ 实体相似度计算正常 (相似度: {sim:.2f}, 类型: {match_type})")
 
 except Exception as e:
@@ -90,7 +90,7 @@ except Exception as e:
 print("\n4. 测试图片处理器功能...")
 
 try:
-    processor  = get_image_processor()
+    processor = get_image_processor()
 
     # 测试图片类型检测（使用模拟数据）
     print(f"   ✓ 支持的图片类型: {list(processor.IMAGE_TYPES.keys())}")
@@ -103,7 +103,7 @@ except Exception as e:
 print("\n5. 测试视频处理器配置...")
 
 try:
-    processor  = get_multimodal_processor()
+    processor = get_multimodal_processor()
 
     print(f"   ✓ 视频目录: {processor.video_dir}")
     print(f"   ✓ 帧目录: {processor.frames_dir}")
@@ -129,11 +129,11 @@ print("\n6. 测试数据库多模态方法...")
 try:
     from db_manager import get_db_manager
 
-    db  = get_db_manager()
+    db = get_db_manager()
 
     # 检查多模态表是否存在
-    conn  = db.get_conn()
-    tables  = ["videos", "video_frames", "images", "multimodal_mentions", "multimodal_entity_links"]
+    conn = db.get_conn()
+    tables = ["videos", "video_frames", "images", "multimodal_mentions", "multimodal_entity_links"]
 
     for table in tables:
         try: