chore: import upstream snapshot with attribution

apps/webapp/app/services/referralSource.server.ts

@@ -0,0 +1,53 @@
+import { createCookie } from "@remix-run/node";
+import { z } from "zod";
+import { prisma } from "~/db.server";
+import { env } from "~/env.server";
+import { telemetry } from "~/services/telemetry.server";
+
+const ReferralSourceSchema = z.enum(["vercel"]);
+
+export type ReferralSource = z.infer<typeof ReferralSourceSchema>;
+
+// Cookie that persists for 1 hour to track referral source during login flow
+export const referralSourceCookie = createCookie("referral-source", {
+  maxAge: 60 * 60, // 1 hour
+  httpOnly: true,
+  sameSite: "lax",
+  secure: env.NODE_ENV === "production",
+});
+
+export async function getReferralSource(request: Request): Promise<ReferralSource | null> {
+  const cookie = request.headers.get("Cookie");
+  const value = await referralSourceCookie.parse(cookie);
+  const parsed = ReferralSourceSchema.safeParse(value);
+  return parsed.success ? parsed.data : null;
+}
+
+export async function setReferralSourceCookie(source: ReferralSource): Promise<string> {
+  return referralSourceCookie.serialize(source);
+}
+
+export async function clearReferralSourceCookie(): Promise<string> {
+  return referralSourceCookie.serialize("", {
+    maxAge: 0,
+  });
+}
+
+export async function trackAndClearReferralSource(
+  request: Request,
+  userId: string,
+  headers: Headers
+): Promise<void> {
+  const referralSource = await getReferralSource(request);
+  if (!referralSource) return;
+
+  headers.append("Set-Cookie", await clearReferralSourceCookie());
+
+  const user = await prisma.user.findUnique({ where: { id: userId } });
+  if (!user) return;
+
+  const userAge = Date.now() - user.createdAt.getTime();
+  if (userAge >= 30 * 1000) return;
+
+  telemetry.user.identify({ user, isNewUser: true, referralSource });
+}