zxbingoo/dsh-minimalist-appearance: Only changes DSH's colors and chat background

This is a DSH persistent appearance plugin maintained by zxbingoo, installed via the native plugin manager. A new "Appearance" entry has been added to the sidebar, providing seven themes: Light, Dark, System, Green, Sea Blue, Warm Sand, and Original. The settings page serves as a static schematic, with clicking triggering an atomic write to save. The plugin only modifies rendering aspects such as conversation background, local background color variables, popup menu material, and sidebar background; it does not alter fonts, font weights, line heights, control sizes, message structures, or interactions. The source code for the current version 0.2.18 includes color compatibility fixes and an adjusted green light theme B color scheme. It runs with the permissions of the current DSH process, and source code and the MIT license must be checked before installation.