DeepSeek Harness Plugin: dsh-arithmetic-series (Arithmetic Series)

`dsh-arithmetic-series` is a DeepSeek Harness (DSH) plugin maintained by uckkk, designed to add mathematical capabilities to sessions. It is implemented in pure Node.js, encapsulating the logic for generating arithmetic sequences into a tool without depending on external APIs. Once installed via `dsh plugin add github:uckkk/dsh-arithmetic-series`, the relevant tool becomes automatically available in sessions, ensuring stable calculation results.