New /profile page

Avatar (initials) + display name, email, admin badge
Account section: email, UID, role, join date, last sign-in
Discord section: link status with username/user ID/linked date, or the get-code flow if unlinked, plus unlink button
Sign out button at the bottom

drb-frontend/components/Nav.tsx

@@ -2,7 +2,7 @@
 
 import { useState } from "react";
 import Link from "next/link";
-import { usePathname } from "next/navigation";
+import { usePathname, useRouter } from "next/navigation";
 import { useUnconfiguredNodes } from "@/lib/useNodes";
 import { useUnacknowledgedAlerts } from "@/lib/useAlerts";
 import { useAuth } from "@/components/AuthProvider";
@@ -49,8 +49,9 @@ function MoonIcon() {
 }
 
 export function Nav() {
-  const { user, isAdmin, signOut } = useAuth();
+  const { user, isAdmin } = useAuth();
   const pathname = usePathname();
+  const router = useRouter();
   const { nodes: pending } = useUnconfiguredNodes();
   const unackedAlerts = useUnacknowledgedAlerts();
   const { theme, toggle } = useTheme();
@@ -101,12 +102,17 @@ export function Nav() {
             {theme === "dark" ? <SunIcon /> : <MoonIcon />}
           </button>
 
-          {/* Sign out (desktop) */}
+          {/* Profile avatar (desktop) */}
           <button
-            onClick={signOut}
-            className="hidden md:block text-sm font-mono text-gray-500 hover:text-gray-300 transition-colors"
+            onClick={() => router.push("/profile")}
+            className={`hidden md:flex items-center justify-center w-7 h-7 rounded-full text-xs font-bold transition-colors ${
+              pathname.startsWith("/profile")
+                ? "bg-indigo-600 text-white"
+                : "bg-gray-800 text-gray-300 hover:bg-gray-700"
+            }`}
+            title="Profile"
           >
-            Sign out
+            {(user?.displayName || user?.email || "?")[0].toUpperCase()}
           </button>
 
           {/* Hamburger (mobile) */}
@@ -154,12 +160,15 @@ export function Nav() {
             </Link>
           ))}
           <div className="border-t border-gray-800 pt-3 mt-1">
-            <button
-              onClick={signOut}
-              className="text-sm font-mono text-gray-500 hover:text-gray-300 transition-colors"
+            <Link
+              href="/profile"
+              onClick={() => setMobileOpen(false)}
+              className={`py-2 text-sm font-mono transition-colors flex items-center gap-2 ${
+                pathname.startsWith("/profile") ? "text-white" : "text-gray-500"
+              }`}
             >
-              Sign out
-            </button>
+              Profile
+            </Link>
           </div>
         </div>
       )}