CSS class migrations: stat-card cursor, view toggle, bulk actions visibility

- Replace stat-card cursor:pointer inline style with CSS rule
- Convert view toggle (table/card) to use .is-hidden CSS class
- Convert bulk-actions and export-dropdown to use .is-visible class
- Add .is-hidden/.is-visible utility rules to dashboard.css
- Remove duplicate lt.keys.initDefaults() call from dashboard.js
- Remove redundant setTimeout from view mode restore
- Add lt.keys.initDefaults() to dashboard.js (was missing entirely)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

views/DashboardView.php

@@ -524,7 +524,7 @@ $nonce = SecurityHeadersMiddleware::getNonce();
     <!-- END OUTER FRAME -->
 
     <!-- Kanban Card View -->
-    <section id="cardView" class="card-view-container" style="display: none;" aria-label="Kanban board view">
+    <section id="cardView" class="card-view-container is-hidden" aria-label="Kanban board view">
         <div class="kanban-board">
             <div class="kanban-column" data-status="Open">
                 <div class="kanban-column-header status-Open">
@@ -992,7 +992,6 @@ $nonce = SecurityHeadersMiddleware::getNonce();
 
         // Stat card click handlers for filtering
         document.querySelectorAll('.stat-card').forEach(card => {
-            card.style.cursor = 'pointer';
             card.addEventListener('click', function() {
                 const classList = this.classList;
                 let url = '/?';