chore: import upstream snapshot with attribution

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

@@ -0,0 +1,25 @@
+import { createCookie } from "@remix-run/node";
+import { env } from "~/env.server";
+
+export type LastAuthMethod = "github" | "google" | "email" | "sso";
+
+// Cookie that persists for 1 year to remember the user's last login method
+export const lastAuthMethodCookie = createCookie("last-auth-method", {
+  maxAge: 60 * 60 * 24 * 365, // 1 year
+  httpOnly: true,
+  sameSite: "lax",
+  secure: env.NODE_ENV === "production",
+});
+
+export async function getLastAuthMethod(request: Request): Promise<LastAuthMethod | null> {
+  const cookie = request.headers.get("Cookie");
+  const value = await lastAuthMethodCookie.parse(cookie);
+  if (value === "github" || value === "google" || value === "email" || value === "sso") {
+    return value;
+  }
+  return null;
+}
+
+export async function setLastAuthMethodHeader(method: LastAuthMethod): Promise<string> {
+  return lastAuthMethodCookie.serialize(method);
+}