dsh-network-proxy: DeepSeek Harness network proxy management plugin

dsh-network-proxy is a network proxy management plugin developed for DeepSeek Harness (DSH), aiming to solve the issue of scattered configurations caused by manually modifying environment variables or relying on system proxies. The plugin adopts the MIT license, centrally managing network traffic via a graphical interface and supports three modes: Follow System, Manual Proxy, and Direct Connection. Configuration changes take effect immediately through DSH's live settings mechanism without requiring a restart. Based on undici, the plugin uniformly manages global requests and intelligently parses system proxy settings on Windows. It requires Node.js 20.18.1 or higher, as well as specific DSH dependency packages. Users can install it via npm and select modes in the settings interface; the manual mode requires entering a valid HTTP/H...