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.
Cleaned up various files by removing unused or redundant import statements to improve code readability and reduce potential confusion. No functional changes were made.
