DeepSeek Harness Plugin Development Manager

`dsh-plugin-dev-manager` is a plugin for DeepSeek Harness (DSH) that manages plugin development environments through isolation mechanisms, ensuring that development failures do not affect stable running instances. Its core features include: creating independent DSH_HOME, ports, and configurations for each Workspace; supporting multi-plugin composition and lifecycle management; providing build verification, secure log reading, and process safety controls; and enabling visual management through the settings page. Developers can create Workspaces via RPC calls and define dependencies using configuration files. This plugin is suitable for scenarios where plugin development is required without interrupting the stable environment.