dsh-darkplus-code: A VS Code Plugin for Controlling Dark+ Syntax Colors and Code Block Font Size

The `dsh-darkplus-code` plugin aims to address the visual issue in DeepSeek Harness (DSH) where code blocks have a fixed font size and a limited color palette. It applies the VS Code Dark+ color scheme and takes over font size calculation logic, supporting either following global settings or independent configuration through Follow, Ratio, and Fixed modes. The plugin only modifies code block styling without affecting other UI elements and supports settings persistence to achieve a more consistent code display.