dsh-prime-agent: A Persistent TypeScript REPL Plugin for DeepSeek Harness

dsh-prime-agent is an RLM-first control plane plugin for the DeepSeek Harness (DSH), providing a persistent TypeScript REPL environment for Prime preset sessions. Unlike the official one-shot semantics, this plugin converges model-visible tools into a single `repl` interface, allowing variables, functions, and object states declared in previous REPL cells to be reused in subsequent cells. Other DSH capabilities such as `tools`, `agents`, and `jobs` are not exposed in the model schema but are preloaded into the cell for direct invocation; attempting to call other tools directly is rejected by the guard. Core capabilities include local composition operations such as `apply_