DSH browser tab favicon reflecting session state

Key features

• Live session state on the tab favicon — the browser-tab icon mirrors idle / running / asking / done (aggregate priority: asking running done idle), so background tabs tell you at a glance what your agents are doing — including ask_user_question prompts and approval / sandbox-escalation waits, which pin the icon to asking.
• colors — an array of hex colors.
• Each state is a collapsible row showing a color dot and a one-line summary (blink · #E5484D ⇄ #FACC15 · 400ms)
• Host plugin with a small browser half: registers routes on the existing webServer — the status JSON endpoint, a static /dsh-web-icon-indicator/base.svg (the whale template), and one tapIndex that injects a small browser script into every served index.html.
• One SVG, recolored & animated in the browser — ships a single whale template (icons/base.svg)