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.

src/tooling/panelStorageDocs.test.mjs

@@ -77,13 +77,14 @@ test('the documented outcomes hold: default, stored open, stored shut, and a sha
   // against the code that decides them.
   const { PanelPositionControls } =
     await import('../ui/panelPositionControls.js');
+  const { presentPanelLocally } = await import('../testSupport/panelState.mjs');
   const html = await readFile(
     path.join(root, 'src/ui/views/panels/CctvPanel.vue'),
     'utf8',
   );
   assert.match(
     html,
-    /<div id="cctv-panel" class="panel-collapsible collapsed"/,
+    /<div id="cctv-panel"[^>]*class="panel-collapsible collapsed"/,
     'the CCTV panel starts collapsed in the markup',
   );
 
@@ -110,7 +111,7 @@ test('the documented outcomes hold: default, stored open, stored shut, and a sha
   };
   try {
     const controls = new PanelPositionControls({
-      syncPanelCollapseButton: () => {},
+      presentPanel: presentPanelLocally,
       layoutRightPanels: () => {},
       syncCctvPanelViewport: () => {},
       showToast: () => {},