added neon auth

lib/auth/server.ts

@@ -0,0 +1,12 @@
+import { createNeonAuth } from "@neondatabase/auth/next/server";
+
+export const auth = createNeonAuth({
+  baseUrl: process.env.NEON_AUTH_BASE_URL!,
+  cookies: {
+    secret: process.env.NEON_AUTH_COOKIE_SECRET!,
+  },
+});
+
+export function getSession() {
+  return auth.getSession();
+}