DeepSeek Harness Plugin: dsh-function-plot

`dsh-function-plot` is a 2D educational plotting plugin for DeepSeek Harness (DSH), designed to address the need for function visualization in model reasoning and presentations. It supports drawing function curves (such as activation functions and distribution charts) and displaying SVG files, with features like card interaction and rendering existing images. It can be installed and enabled with simple commands and offers flexible configuration. It is especially suitable for development and teaching scenarios that frequently require mathematical derivations or architecture diagram presentations.