dsh-instruction-memory: DSH Long-Term Instruction Memory Plugin

`dsh-instruction-memory` is a plugin for DeepSeek Harness (DSH), designed to maintain stable system instructions through a plugin-based architecture. It allows users to manage long-term instructions in settings and supports automatic injection, multi-instance concurrency protection, external file synchronization, and data export and import. Users must install it via the command line and configure its priority and applicable scenarios on the settings page. The plugin requires Node.js >= 20, and the injected content is limited to 40,000 characters. Before installation, ensure compatibility with the host version and be aware of security risks when running in non-loopback address environments.