dsh-fusion-pixel-font: Replace DSH's Interface and Code Fonts with the Fusion Pixel 12px Pixel Font

The `dsh-fusion-pixel-font` plugin is maintained by TableRogue and is designed to uniformly replace the interface and code text in the DeepSeek Harness Web GUI with the Fusion Pixel 12px font. The plugin hosts font files via same-origin delivery, requires no external network dependencies, and supports system font fallback. It takes effect automatically after installation without requiring a rebuild, supports command-based verification and uninstallation, and is licensed under the MIT License.