fix(ui): a page's sub-tab is remembered per browser tab, not forever

Settings, Configuration, Statistics and Users kept the last sub-tab in localStorage, so every
fresh tab opened Configuration on "Plex" as if that were its home. useTabPersistedState keeps it
in sessionStorage (account-scoped): a reload and a trip to another page keep it, a new tab starts
on the first sub-tab. The pre-selects (a Review link, the Google-link return) write the same store;
a value an older build left in localStorage is cleared on first read.

frontend/src/components/AdminUsers.tsx

@@ -41,7 +41,7 @@ import AccountPanel from "./AccountPanel";
 import { useConfirm } from "./confirmContext";
 import Tabs from "./ui/Tabs";
 import { useTabPanel } from "./ui/tabPanel";
-import { useAccountPersistedState } from "../lib/storage";
+import { useTabPersistedState } from "../lib/storage";
 import { PageToolbar } from "./ui/PageShell";
 import { useMe } from "../lib/useMe";
 import { notifyActionError, notifyKnownFailure } from "../lib/actionErrors";
@@ -69,7 +69,7 @@ const ROW_OPEN =
 export default function AdminUsers() {
   const me = useMe();
   const { t } = useTranslation();
-  const [tab, setTab] = useAccountPersistedState(ADMIN_USERS_TAB_KEY, "roles");
+  const [tab, setTab] = useTabPersistedState(ADMIN_USERS_TAB_KEY, "roles");
   const panel = useTabPanel();
   const tabs = [
     { id: "roles", label: t("users.tabs.roles") },