Hi y'all. I have created a project to test out this problem I am having where sometimes the redirect does not work as expected or at least not as I understand it.
Say we have a redirect/route.ts that looks like:

export async function GET(request: NextRequest) {
  // user is not logged in
  const session = await getSession();
  if (!session) {
    redirect(`/login?next=${request.nextUrl.pathname}`);
  }

  redirect("/setup");
}

The login action:

"use server";

import { cookies } from "next/headers";
import { encrypt } from "./app/lib";
import { redirect } from "next/navigation";

export async function loginAction(formData: FormData) {
  const user = {
    username: formData.get("username"),
    password: formData.get("password"),
  };
  const expires = new Date(Date.now() + 7 * 24 * 60 * 60 * 1000); // a week
  const session = await encrypt({ user, expires });

  cookies().set("session", session, { expires, httpOnly: true });

  const redirectTo = formData.get("next") as string;

  if (redirectTo) {
    redirect(redirectTo);
  }

  redirect("/dashbord");
}

If in redirect/route.ts I remoe the bit that appends the query param ?next everything works OK, it redirects to /setup without an issue and the URL on client changes, but for some reason even with this simple example when I do add it and create this system that does not forget where it comes from, I find myself with the URL not changing aka it shows /redirect although the content was correctly loaded as /setup

Somewhere I read that this would only change where the answer comes from not the URL, for that that should be done in client but does it? Because as I said, it works fine and the URL changes when the next query param is not considered and a simple redirection is done. Also, tried to change this to middleware and the problem remains the same. Could someone please point to me what is going wrong here?

Thank you so much