dsh-filetransfer: Local File Draft and Deliverable Downloads in DeepSeek Harness Web

`dsh-filetransfer` is a localized file-processing plugin for DeepSeek Harness Web, designed to address challenges in uploading, previewing, and downloading deliverables for non-image files in web environments. It offers file draft management, drag-and-drop upload, Word/Excel rendering, and local loopback deliverable downloads. Installation requires Node.js 22.19+, and the plugin binds to a local port by default while supporting file references via XML tags. Its core is secure and reliable, with no dependency on third-party platforms, making it a complete solution for document interaction in web-based agent development.