dsh-page-zoom: DeepSeek Harness Page Zoom Plugin

The `dsh-page-zoom` plugin addresses DeepSeek Harness’s default font-zoom-only limitation by enabling page zoom with Ctrl + mouse wheel. It uses the CSS `zoom` property to scale the entire interface (including fixed UI elements) from 30% to 200% and persists settings in `localStorage`. A real-time zoom ratio is displayed in the bottom-right corner. The installation command is `dsh plugin --profile desktop add github:Centaurea5547196/dsh-page-zoom`.