refactor: 移除WebSocket同步功能及相关代码

feat(theme): 增强侧边栏选中项样式配置
style: 优化主题变量和样式覆盖逻辑
chore: 清理未使用的依赖和配置文件

electron-builder.yml

@@ -49,8 +49,5 @@ linux:
 appImage:
   artifactName: ${name}-${version}.${ext}
 npmRebuild: false
-publish:
-  provider: generic
-  url: https://example.com/auto-updates
 electronDownload:
   mirror: https://npmmirror.com/mirrors/electron/