Add lt.autoRefresh, fix showToast in admin, clean up inline styles

- Replace all 8 showToast() calls in ApiKeysView.php with lt.toast.*
  — all toast calls in the codebase now use lt.toast directly
- Add .duplicate-list, .duplicate-meta, .duplicate-hint CSS classes to
  dashboard.css; replace inline styles in duplicate detection JS with them
- Add dashboardAutoRefresh() using lt.autoRefresh — reloads page every
  5 minutes, skipping if a modal is open or user is typing in an input
- Add REFRESH button to dashboard header that triggers lt.autoRefresh.now()
  for immediate manual refresh with timer restart

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

views/DashboardView.php

@@ -102,6 +102,7 @@ $nonce = SecurityHeadersMiddleware::getNonce();
                         </div>
                     </div>
                 <?php endif; ?>
+                <button class="btn" style="font-size:0.75rem; padding: 0.2rem 0.5rem;" data-action="manual-refresh" title="Refresh now (auto-refreshes every 5 min)" aria-label="Refresh dashboard">REFRESH</button>
                 <button class="settings-icon" title="Settings (Alt+S)" data-action="open-settings" aria-label="Settings">[ CFG ]</button>
             <?php endif; ?>
         </div>
@@ -861,6 +862,10 @@ $nonce = SecurityHeadersMiddleware::getNonce();
                     openSettingsModal();
                     break;
 
+                case 'manual-refresh':
+                    lt.autoRefresh.now();
+                    break;
+
                 case 'close-settings':
                     closeSettingsModal();
                     break;