dsh-web-search-router: Multi-Source Web Search Routing Plugin for DeepSeek Harness

`dsh-web-search-router` is a multi-provider search routing plugin for DeepSeek Harness (DSH), designed to address the instability of relying on a single search source. It enables users to switch among multiple search engines—such as SearXNG, DeepSeek Search, and Tavily—through priority-based routing and automatic fallback mechanisms, while also providing cooldown configuration, log cleanup, and secure credential management. The plugin is compatible with DSH versions 0.1.0-rc.6 and 0.1.1-rc.x, and is installed via the command line and configured through the DSH settings interface.