dsh-utility-tools: Adding file drag-and-drop and text referencing to DSH chat

dsh-utility-tools is an input-side utility plugin for DSH conversations, maintained by sharkymew and licensed under the MIT license. The plugin primarily addresses two issues: first, it supports dragging and dropping arbitrary files into the chat area, allowing for the preview of filenames and sizes before sending, as well as individual removal; second, it allows users to select conversation text and add it to the beginning of the pending message as a blockquote. The plugin provides two installation methods: static mounting and dynamic loading. The static version installs to the web profile via a single command and utilizes HTTP routing for uploading attachments; the dynamic version loads with zero dependencies using `cordis_define` and runs in-process. It is applicable for scenarios in web or Electron environments where file attachments or context references need to be added. Please note that standard browsers cannot access real disk paths, and the single file limit is 8MB.