feat(dees-simple-appdash): add global message banners with actions and dismissal support

ts_web/elements/00group-simple/dees-simple-appdash/dees-simple-appdash.demo.ts

@@ -1,5 +1,5 @@
 import { html, DeesElement, customElement, css, cssManager } from '@design.estate/dees-element';
-import type { IView } from './dees-simple-appdash.js';
+import type { IView, IGlobalMessage } from './dees-simple-appdash.js';
 import '../../00group-form/dees-form/dees-form.js';
 import '../../00group-input/dees-input-text/dees-input-text.js';
 import '../../00group-input/dees-input-checkbox/dees-input-checkbox.js';
@@ -263,6 +263,44 @@ export const demoFunc = () => html`
     <dees-simple-appdash
       name="My Application"
       terminalSetupCommand="echo 'Welcome to the terminal!'"
+      .globalMessages=${[
+        {
+          id: 'update',
+          type: 'info',
+          message: 'A new version (v3.50.0) is available with performance improvements and bug fixes.',
+          dismissible: true,
+          actions: [
+            {
+              name: 'Update Now',
+              iconName: 'lucide:download',
+              action: () => alert('Updating...'),
+            },
+            {
+              name: 'Release Notes',
+              action: () => alert('Opening release notes...'),
+            },
+          ],
+        },
+        {
+          id: 'maintenance',
+          type: 'warning',
+          message: 'Scheduled maintenance window: April 5, 2026 02:00–06:00 UTC. Some services may be temporarily unavailable.',
+          dismissible: true,
+        },
+        {
+          id: 'critical',
+          type: 'error',
+          message: 'Your SSL certificate expires in 3 days. Renew now to avoid service disruption.',
+          dismissible: false,
+          actions: [
+            {
+              name: 'Renew Certificate',
+              iconName: 'lucide:shieldCheck',
+              action: () => alert('Renewing certificate...'),
+            },
+          ],
+        },
+      ] as IGlobalMessage[]}
       .viewTabs=${[
         {
           name: 'Dashboard',