dsh-vault-plugin: DSH Frontend Privacy Lock Plugin

The DeepSeek Harness plugin `dsh-vault-plugin` enables Web and Desktop profiles to lock Workspaces or Sessions directly from the sidebar, supporting password policies, auto-lock, and session invalidation. This plugin is community-maintained, does not encrypt raw data when stored on disk, and does not rely on external services. After installation, you need to manage password groups in Settings and pay attention to version compatibility and permission management.