dsh-deepseek-status-pill: Add a service status indicator to the DSH Desktop top bar

This DSH client plugin, maintained by Vip4pt, features a resident status capsule in the top bar of DeepSeek Harness Desktop. A green light indicates normal service, a yellow light with a breathing glow indicates a failure or read failure, while the initial check appears gray. It exclusively subscribes to the public Atom feed at https://status.deepseek.com/feed.atom, without scraping HTML or calling private interfaces; it has zero dependencies and requires no configuration. Hovering or focusing on the tab expands the detail panel, and pressing Esc closes it. The Host side handles Atom parsing, 45-second snapshot caching, and failure fallback, preserving the last successful snapshot; the Browser side polls every 60 seconds and locates according to the Windows top bar. Same-origin routing employs custom headers and Origin/Sec-Fetch-Site verification. The plugin is designed only for Windows Desktop (dsh >= 0.2.1-rc.5) and remains silent outside the Windows top bar. Please check the source code and MIT license before installation.