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/adminPendingAccess.dom.test.tsx

@@ -48,7 +48,7 @@ vi.mock("../lib/useMe", () => ({ useMe: () => meMock }));
 vi.mock("./ui/Tabs", () => ({ default: () => null }));
 vi.mock("../lib/storage", async (importOriginal) => ({
   ...(await importOriginal<typeof import("../lib/storage")>()),
-  useAccountPersistedState: () => ["access", () => {}],
+  useTabPersistedState: () => ["access", () => {}],
 }));
 
 const pendingMock = vi.fn();