DeepSeek Harness Plugin Hot-Swap and Manifest Manager

dsh-plugin-hotplug is the hot-pluggable manager for DeepSeek Harness (DSH), designed to address the limitation that the official plugin manifest is read-only and cannot be switched at runtime. It provides source-aware layered manifests, supports instant enable or disable actions for the current profile and third-party bundles, and persists the resulting state. By leveraging the Cordis Loader lifecycle, it enables safe hot unloading and recovery, while also incorporating state separation and security protection mechanisms. After installation, users can replace the read-only manifest through the settings page, making plugin debugging and configuration management more convenient.