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/narrow-card.tsx

@@ -0,0 +1,22 @@
+import { Card, CardContent, CardDescription, CardHeader, CardTitle } from "@/components/ui/card";
+
+/** A small centered card: sign-in, sign-up, device sign-in, errors. */
+export function NarrowCard({
+  title,
+  description,
+  children,
+}: {
+  title: React.ReactNode;
+  description?: React.ReactNode;
+  children?: React.ReactNode;
+}) {
+  return (
+    <Card className="mx-auto w-full max-w-sm">
+      <CardHeader>
+        <CardTitle className="text-xl">{title}</CardTitle>
+        {description && <CardDescription>{description}</CardDescription>}
+      </CardHeader>
+      {children && <CardContent>{children}</CardContent>}
+    </Card>
+  );
+}