DeepSeek Harness Aggregated Search Plugin dsh-websearch

`@240xu/dsh-websearch` is a plugin that resolves the `WEB_PROVIDER_AMBIGUOUS` error in the native Web Search plugin. It registers the unique `unified` provider, aggregates concurrent searches across 11 backends, and supports URL deduplication and zero-configuration backends. Installation requires modifying the configuration file, and API keys can be configured via environment variables or the settings panel. The plugin includes fault tolerance, ensuring that a single backend failure does not affect overall operation, and provides detailed logs for diagnosing backend status.