dsh-font-enhancer: Customize DSH UI Font and Color by Region

`dsh-font-enhancer` is a DSH client plugin that allows individual adjustment of Chinese and English font family, font size, line height, color, and font weight per area (such as the message area and sidebar). It also supports global settings and box selection. Users can save named themes, generate random color schemes or fonts, and download cute fonts. The plugin runs entirely on the client side, supports both DSH web and desktop, and stores settings locally, so they persist across page refreshes.