Refactor web search plugin and clean up code

Refactored the web search plugin by removing the old Bing search implementation and reorganizing the plugin structure. Introduced modular search engine classes under 'web_search_tool/engines' and utility tools under 'web_search_tool/tools' and 'web_search_tool/utils'. Updated references and initialization logic to support multiple search engines and improved maintainability. Also performed minor code cleanups and replaced 'except ...: pass' with 'except ...: ...' for brevity.

src/chat/utils/utils_image.py

@@ -381,8 +381,7 @@ class ImageManager:
                     # 确保是RGB格式方便比较
                     frame = gif.convert("RGB")
                     all_frames.append(frame.copy())
-            except EOFError:
-                pass  # 读完啦
+            except EOFError: ... # 读完啦
 
             if not all_frames:
                 logger.warning("GIF中没有找到任何帧")