show proper 404 page for missing custom pages instead of redirecting

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

test/berrypod_web/live/shop/custom_page_test.exs

@@ -49,8 +49,10 @@ defmodule BerrypodWeb.Shop.CustomPageTest do
       :ok
     end
 
-    test "redirects anonymous users to home", %{conn: conn} do
-      {:error, {:live_redirect, %{to: "/"}}} = live(conn, "/draft-page")
+    test "returns 404 for anonymous users", %{conn: conn} do
+      assert_raise BerrypodWeb.NotFoundError, fn ->
+        live(conn, "/draft-page")
+      end
     end
 
     test "renders for admin users", %{conn: conn, user: user} do
@@ -61,8 +63,10 @@ defmodule BerrypodWeb.Shop.CustomPageTest do
   end
 
   describe "nonexistent page" do
-    test "redirects to home with flash", %{conn: conn} do
-      {:error, {:live_redirect, %{to: "/"}}} = live(conn, "/does-not-exist")
+    test "returns 404", %{conn: conn} do
+      assert_raise BerrypodWeb.NotFoundError, fn ->
+        live(conn, "/does-not-exist")
+      end
     end
   end