Website: Next.js app for accounts, linking, who's online, device sign-in and the console

apps/web: Next.js 16 (App Router), Tailwind 4 and shadcn/ui, light and dark from the system. Pages render on the
server and call the API with Eden Treaty (typed by @t5de/api), forwarding the visitor's cookie; forms use server
actions; sign-up, sign-in and sign-out use Better Auth's React client. /api is rewritten to the API so its cookies
are first-party. Who's online follows the API's event stream (Next's gzip is off: it held the stream back).
Standalone output with a Dockerfile; deploys to Vercel as is.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

apps/web/components/header-client.tsx

@@ -0,0 +1,52 @@
+"use client";
+import Link from "next/link";
+import { usePathname, useRouter } from "next/navigation";
+import { useState } from "react";
+import { Button } from "@/components/ui/button";
+import { authClient } from "@/lib/auth-client";
+import { cn } from "@/lib/utils";
+
+/** A link in a navigation bar, marked when it's the current page (or, unless exact, a page under it). */
+export function NavLink({
+  href,
+  exact = false,
+  children,
+}: {
+  href: string;
+  exact?: boolean;
+  children: React.ReactNode;
+}) {
+  const pathname = usePathname();
+  const here = pathname === href || (!exact && pathname.startsWith(href + "/"));
+  return (
+    <Link
+      href={href}
+      aria-current={here ? "page" : undefined}
+      className={cn(
+        "rounded-md px-2.5 py-1.5 text-muted-foreground transition-colors hover:text-foreground",
+        here && "bg-muted text-foreground",
+      )}
+    >
+      {children}
+    </Link>
+  );
+}
+
+export function SignOutButton() {
+  const router = useRouter();
+  const [pending, setPending] = useState(false);
+  return (
+    <Button
+      variant="outline"
+      disabled={pending}
+      onClick={async () => {
+        setPending(true);
+        await authClient.signOut();
+        router.push("/");
+        router.refresh();
+      }}
+    >
+      {pending ? "Signing out…" : "Sign out"}
+    </Button>
+  );
+}