Enhance Download Functionality with Proxy and Progress Tracking

- Implemented advanced download utility with proxy support for SOCKS5 and HTTP protocols
- Added progress tracking with human-readable file size and download percentage
- Updated go.mod and go.sum to include new dependencies for proxy and networking
- Created flexible proxy client generation for different proxy types
- Improved error handling and logging in download process

agent-wdd/cmd/root.go

@@ -112,6 +112,7 @@ func Execute() {
 		Use:   "download",
 		Short: "文件下载管理",
 	}
+
 	addDownloadSubcommands(downloadCmd)
 
 	helpCmd := &cobra.Command{