dsh-graphify: Native Code Knowledge Graph Plugin for DeepSeek Harness

The `dsh-graphify` plugin for DeepSeek Harness (DSH) natively connects to a local knowledge graph engine, providing agents with session-aware project parsing, code change tracking, and dual-mode (Compact/Full) graph query tools. It supports incremental updates and full builds, features local runtime resilience, and helps agents construct structured code maps. Installation requires Node.js, Python, and uv, and has been tested on macOS/Ubuntu; Windows is unverified. The `/graphify` command builds or refreshes the graph, `update` processes only code changes, and documentation changes require a full rebuild.