dsh-desktop-window: A Standalone Window Plugin for DSH

`dsh-desktop-window` is a DeepSeek Harness (DSH) plugin designed to run the DSH Web UI in a standalone application window, addressing the accumulation of browser tabs and the mixing of browsing history. Its core features include automatic and manual window switching, branding injection, environment isolation through a separate configuration file, and cross-platform support. It runs in Chromium's `--app` mode to ensure isolation from everyday browsing. Installation requires restarting the `dsh web` process, and the configuration file supports auto-launch and persistent settings. Attention should be paid to taskbar icon display and runtime considerations.