feat: detect duplicates in csv

web/admin.html

@@ -90,7 +90,7 @@
         <div class="mt-auto pt-3" style="border-top:1px solid var(--border);">
             <div class="nav-link-custom" style="cursor:default;">
                 <i class="fa-solid fa-circle-user fa-fw"></i>
-                <span style="font-size:0.82rem;">Admin</span>
+                <span class="nav-username" style="font-size:0.82rem;">User</span>
             </div>
         </div>
     </div>
@@ -245,7 +245,21 @@
 
         async function loadAdmin() {
             try {
-                const data = await fetch('/api/admin.php').then(r => r.json());
+                const r = await fetch('/api/admin.php', { redirect: 'manual' });
+                if (r.type === 'opaqueredirect') { window.location.reload(); return; }
+                if (!r.ok) { window.location.replace('index.html'); return; }
+                const data = await r.json();
+
+                if (!data.is_admin) {
+                    window.location.replace('index.html');
+                    return;
+                }
+
+                document.querySelectorAll('.admin-nav-link').forEach(el => el.classList.remove('d-none'));
+                const name = data.name || data.username;
+                if (name) {
+                    document.querySelectorAll('.nav-username').forEach(el => { el.textContent = name; });
+                }
 
                 document.getElementById('sandboxToggle').checked = data.sandbox_mode;
                 document.getElementById('sandboxBanner').style.display = data.sandbox_mode ? '' : 'none';
@@ -359,6 +373,7 @@
         // ─── Init ────────────────────────────────────────────────────────────────────
 
         loadAdmin();
+        document.addEventListener('visibilitychange', () => { if (document.visibilityState === 'visible') loadAdmin(); });
     </script>
 </body>