Show Admin nav only when GET /admin succeeds

Probe Authelia-protected /admin with credentials; keep the public
site free of admin links for anonymous visitors.

client/src/components/Layout.scss

@@ -55,6 +55,11 @@
     opacity: 0.85;
   }
 
+  &__admin {
+    color: var(--accent) !important;
+    font-weight: 500;
+  }
+
   &__burger {
     display: none;
     width: 40px;

client/src/components/Layout.tsx

@@ -1,17 +1,30 @@
 import { useEffect, useState } from "react";
 import { Link, NavLink, Outlet, useLocation } from "react-router-dom";
 import { api, type SiteSettings } from "../lib/api";
+import { canAccessAdmin } from "../lib/adminAccess";
 import "./Layout.scss";
 
 export function Layout() {
   const [site, setSite] = useState<SiteSettings | null>(null);
   const [menuOpen, setMenuOpen] = useState(false);
+  const [showAdmin, setShowAdmin] = useState(false);
   const location = useLocation();
 
   useEffect(() => {
     api.site().then(setSite).catch(() => setSite({ name: "jmartgraphix" }));
   }, []);
 
+  // Only surface Admin when Traefik/Authelia already allows GET /admin
+  useEffect(() => {
+    let cancelled = false;
+    canAccessAdmin().then((ok) => {
+      if (!cancelled) setShowAdmin(ok);
+    });
+    return () => {
+      cancelled = true;
+    };
+  }, [location.pathname]);
+
   useEffect(() => {
     setMenuOpen(false);
   }, [location.pathname]);
@@ -47,6 +60,11 @@ export function Layout() {
             >
               ArtStation
             </a>
+            {showAdmin && (
+              <NavLink to="/admin" className="site-header__admin">
+                Admin
+              </NavLink>
+            )}
           </nav>
         </div>
       </header>

client/src/lib/adminAccess.ts

@@ -0,0 +1,24 @@
+/**
+ * Probe Traefik/Authelia protection on /admin.
+ * Returns true only when a same-origin GET succeeds (HTTP 200),
+ * meaning the visitor is already authenticated for admin.
+ * Failures (401/403/302/network) keep the public site admin-free.
+ */
+export async function canAccessAdmin(): Promise<boolean> {
+  try {
+    const res = await fetch("/admin", {
+      method: "GET",
+      credentials: "include",
+      redirect: "manual",
+      cache: "no-store",
+      headers: { Accept: "text/html" },
+    });
+    // opaqueredirect (0) = browser blocked reading a cross-origin redirect
+    // 3xx with redirect:manual also means not authorized for the resource
+    if (res.type === "opaqueredirect") return false;
+    if (res.status >= 300 && res.status < 400) return false;
+    return res.status === 200;
+  } catch {
+    return false;
+  }
+}

client/src/pages/HomePage.tsx

@@ -90,8 +90,7 @@ export function HomePage() {
         </div>
         {recent.length === 0 ? (
           <p className="home-empty">
-            Projects will appear here once published. Use the{" "}
+            Projects will appear here once published.
-            <Link to="/admin">admin panel</Link> to add work, or import from ArtStation.
           </p>
         ) : (
           <div className="project-grid">