dsh-model-router: A Reasoning Effort Routing Plugin for DeepSeek Harness

`dsh-model-router` is a DeepSeek Harness plugin designed to automate the management of model reasoning effort and model switching. It supports Flash-only reasoning effort routing, model pool management (including cost tiers and vision tags), task presets (with keyword matching and weight configuration), and Composer UI integration. It can automatically allocate reasoning effort based on task difficulty and intelligently route models using semantic classification or keyword matching. When using the plugin, thinking mode must remain enabled, and source code modifications require a full application restart.