feat(panels): render each panel's state classes from the store

A panel's collapsed, dock-pinned, dock-pinned-top, layout-auto-collapsed
and accordion-collapsed classes are drawn by its root's v-panel-state from
the gev-panel-chrome store. PanelChrome, its restore, the layout
controller, both rails and the side accordion present each panel's state
there instead of writing its classes; the rails call onCollapse(panel,
{collapsed, auto}). The directive applies a change in a synchronous
watcher, since the rails measure a panel in the task that opens or closes
it.

Destroying the chrome inside Cockpit now puts back the panels Cockpit's
entry closed while it can still present them. Without a shell, the voice
tools' set_panel_open reports that there is no panel to open. QA scripts
present the states they set instead of writing the classes.

scripts/qa-weather-journey.mjs

@@ -261,7 +261,7 @@ try {
     for (const [id, entry] of gev.dataManager.layers)
       if (entry.enabled)
         await gev.dataManager.setEnabled(id, false, { origin: 'user' });
-    document.querySelector('#data-panel')?.classList.remove('collapsed');
+    gev.styleManager._presentPanel('data-panel', { collapsed: false });
   });
 
   // 1. Earth view, clean.