Harden dashboard realtime state and controls

tests/dashboard/route-error-boundary.test.tsx

@@ -0,0 +1,10 @@
+// @vitest-environment jsdom
+import { describe, expect, it } from 'vitest';
+import { createDashboardRoutes } from '../../apps/dashboard/src/app/router.js';
+
+describe('dashboard route error boundary', () => {
+  it('protects the application shell from route rendering failures', () => {
+    const root = createDashboardRoutes()[0];
+    expect(root?.errorElement).toBeTruthy();
+  });
+});