feat(dashboard): boarding-pass hero, atlas row, live widgets + modal portal fix

Reworked dashboard layout: boarding-pass hero with hover + days-left countdown, atlas stats row with real flags, searchable currency widget, editable timezone widget, new-trip FAB. Modals now portal to document.body to avoid inheriting dashboard-scoped button/font styles.

client/src/components/shared/ConfirmDialog.tsx

@@ -1,4 +1,5 @@
 import React, { useEffect, useCallback } from 'react'
+import ReactDOM from 'react-dom'
 import { AlertTriangle } from 'lucide-react'
 import { useTranslation } from '../../i18n'
 
@@ -38,7 +39,7 @@ export default function ConfirmDialog({
 
   if (!isOpen) return null
 
-  return (
+  return ReactDOM.createPortal(
     <div
       className="fixed inset-0 z-[10000] flex items-center justify-center px-4 trek-backdrop-enter"
       style={{ backgroundColor: 'rgba(15, 23, 42, 0.5)', paddingBottom: 'var(--bottom-nav-h)' }}
@@ -87,6 +88,7 @@ export default function ConfirmDialog({
         </div>
       </div>
 
-    </div>
+    </div>,
+    document.body
   )
 }