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>

assets/css/dashboard.css

@@ -4642,6 +4642,32 @@ table td:nth-child(4) {
     border-top: 1px solid var(--terminal-green);
 }
 
+/* ===== DUPLICATE DETECTION LIST ===== */
+
+.duplicate-list {
+    margin: 0;
+    padding-left: 1.5rem;
+    color: var(--terminal-green);
+}
+
+.duplicate-list li {
+    margin-bottom: 0.5rem;
+}
+
+.duplicate-list a {
+    color: var(--terminal-green);
+}
+
+.duplicate-meta {
+    color: var(--terminal-amber);
+}
+
+.duplicate-hint {
+    margin-top: 0.5rem;
+    font-size: 0.85rem;
+    color: var(--terminal-green-dim);
+}
+
 /* ===== INLINE ALERT BOXES ===== */
 
 .inline-error {