dsh-skin-blue-whale: Blue Whale Leaping Sea Theme Plugin for dsh Web UI

`dsh-skin-blue-whale` is a "Blue Whale Leaping into the Sea" theme plugin based on DSH Web UI, licensed under the MIT License. This plugin offers theme customization via a plugin format, supporting one-click installation and uninstallation, with automatic style restoration and no residual traces after uninstallation. Its core features include replicating the blue-white gradient background of the official DeepSeek website and adapting to dark mode; utilizing the official whale logo to render visual elements with effects such as splashes and ripples, and supporting adaptive display positions based on home page empty sessions or chat scenarios; uniformly applying Blue Whale Blue color tokens to various interface components; and respecting the system's preference for reducing motion. The prerequisites for installation are Node 20+, pnpm, and dsh version 0.1.0-rc.6 or higher. Users need to clone the repository to a path without spaces and execute `dsh plugin --p...`