feat(ui): render the Cockpit Contact card from a store

The Cockpit controller no longer writes the Contact card's scope,
navigation state, cohort counts, nearest contact, bearing, uncertainty,
update time or weather toggle: it keeps them as plain state, starting
from cockpitContextState.js, and publishes a copy to the gev-cockpit
store, and a new CockpitContext component renders it. A lost contact
still holds its last readout. The weather toggle flips from that state,
not the button's attribute. The card's visibility, collapse and layout
stay with the controller. The controller's publishBrief option becomes
a publish object, one entry per Cockpit view.

docs/VUE-MIGRATION.md

@@ -128,12 +128,17 @@ They contain no application state.
    backdrop to the end of the page from the first publish until the shell
    is destroyed; the shell takes their clicks from the document), then
    Cockpit (in progress: `CockpitBriefing` renders the briefing card's
-   pages, cycle toggle, regional news and local conditions from the
-   `gev-cockpit` store that the Cockpit controller publishes to, starting
-   from `cockpitBriefPages.js`, which both read; the controls keep the
-   controller's listeners, and the route card and signal list keep their
-   owners' bindings for now). Layers that write into the right rail
-   directly gain a slot instead.
+   pages, cycle toggle, regional news and local conditions, and
+   `CockpitContext` the Contact card's scope, navigation, counts, nearest
+   contact and weather toggle, from the `gev-cockpit` store that the Cockpit
+   controller publishes to, starting from `cockpitBriefPages.js` and
+   `cockpitContextState.js`, which both read; the controls keep the
+   controller's listeners, and the cards' visibility, collapse and layout
+   stay with the controller. The signal rows, the route card, the
+   instruments and the radio controls follow; the signal rows become a
+   component that keeps their focus-safe reorder, since a keyed Vue list
+   would move the focused row and drop focus several times a second).
+   Layers that write into the right rail directly gain a slot instead.
 
 4. **Cleanup.** The build-time template expansion and the attribute
    translation pass are retired once nothing uses them. Hosts register panels