feat(scheduler): live admin Scheduler dashboard + reusable poll hook (HU/EN/DE)

New admin Scheduler page (left-nav entry) with a live, self-refreshing view of
job activity, queued work and quota. Polling is factored into a reusable
useLiveQuery hook (pauses when the tab is unfocused) that the notification bell
and future yt-dlp job queue will reuse instead of re-implementing.

frontend/src/App.tsx

@@ -27,6 +27,7 @@ import Feed from "./components/Feed";
 import Channels, { type ChannelStatusFilter } from "./components/Channels";
 import Playlists from "./components/Playlists";
 import Stats from "./components/Stats";
+import Scheduler from "./components/Scheduler";
 import SettingsPanel from "./components/SettingsPanel";
 import OnboardingWizard from "./components/OnboardingWizard";
 import { shouldAutoOpenOnboarding } from "./lib/onboarding";
@@ -62,7 +63,8 @@ function loadInitialPage(): Page {
     stored === "channels" ||
     stored === "stats" ||
     stored === "playlists" ||
-    stored === "settings"
+    stored === "settings" ||
+    stored === "scheduler"
   )
     return stored;
   return "feed";
@@ -271,6 +273,8 @@ export default function App() {
             />
           ) : page === "stats" && meQuery.data!.role === "admin" ? (
             <Stats />
+          ) : page === "scheduler" && meQuery.data!.role === "admin" ? (
+            <Scheduler />
           ) : page === "playlists" ? (
             <Playlists canWrite={meQuery.data!.can_write} />
           ) : page === "settings" ? (

frontend/src/components/Header.tsx

@@ -78,7 +78,9 @@ export default function Header({
               ? t("header.account.playlists")
               : page === "settings"
                 ? t("settings.title")
-                : t("header.channelManager")}
+                : page === "scheduler"
+                  ? t("header.scheduler")
+                  : t("header.channelManager")}
         </div>
       )}
 

frontend/src/components/NavSidebar.tsx

@@ -3,6 +3,7 @@ import { createPortal } from "react-dom";
 import { useTranslation } from "react-i18next";
 import { useQuery } from "@tanstack/react-query";
 import {
+  Activity,
   BarChart3,
   ChevronLeft,
   ChevronRight,
@@ -109,8 +110,10 @@ export default function NavSidebar({
     { page: "channels", icon: Tv, label: t("header.account.channels") },
     { page: "playlists", icon: ListVideo, label: t("header.account.playlists") },
   ];
-  if (me.role === "admin")
+  if (me.role === "admin") {
     items.push({ page: "stats", icon: BarChart3, label: t("header.account.stats") });
+    items.push({ page: "scheduler", icon: Activity, label: t("header.account.scheduler") });
+  }
 
   const rowBase =
     "w-full flex items-center gap-3 rounded-lg px-2.5 py-2 text-sm transition";

frontend/src/components/Scheduler.tsx

@@ -0,0 +1,273 @@
+import { useEffect, useState } from "react";
+import { useTranslation } from "react-i18next";
+import { useMutation, useQueryClient } from "@tanstack/react-query";
+import {
+  Activity,
+  AlertTriangle,
+  Clock,
+  Database,
+  Gauge,
+  Pause,
+  Play,
+  RadioTower,
+} from "lucide-react";
+import { api, type SchedulerJob, type SchedulerStatus } from "../lib/api";
+import { useLiveQuery } from "../lib/useLiveQuery";
+import { relativeTime } from "../lib/format";
+import { notify } from "../lib/notifications";
+import Tooltip from "./Tooltip";
+
+const POLL_MS = 4000;
+
+// Seconds until an ISO instant (negative = past).
+function secsUntil(iso: string | null): number | null {
+  if (!iso) return null;
+  return Math.round((new Date(iso).getTime() - Date.now()) / 1000);
+}
+
+function fmtCountdown(s: number): string {
+  if (s <= 0) return "now";
+  if (s < 60) return `${s}s`;
+  const m = Math.floor(s / 60);
+  if (m < 60) return `${m}m ${s % 60}s`;
+  const h = Math.floor(m / 60);
+  return `${h}h ${m % 60}m`;
+}
+
+function StatusDot({ job }: { job: SchedulerJob }) {
+  const color = job.running
+    ? "bg-accent animate-pulse"
+    : job.status === "ok"
+      ? "bg-emerald-500"
+      : job.status === "error"
+        ? "bg-red-500"
+        : job.status === "skipped"
+          ? "bg-amber-500"
+          : "bg-border";
+  return <span className={`inline-block w-2.5 h-2.5 rounded-full shrink-0 ${color}`} />;
+}
+
+function JobRow({ job }: { job: SchedulerJob }) {
+  const { t } = useTranslation();
+  const next = secsUntil(job.next_run);
+  return (
+    <div className="glass-card rounded-xl p-3 flex items-center gap-3">
+      <StatusDot job={job} />
+      <div className="min-w-0 flex-1">
+        <div className="text-sm font-medium truncate">
+          {t(`scheduler.jobs.${job.id}`, job.id)}
+          <span className="text-muted font-normal">
+            {" "}
+            · {t("scheduler.everyMin", { count: job.interval_minutes })}
+          </span>
+        </div>
+        <div className="text-[11px] text-muted truncate">
+          {job.running
+            ? t("scheduler.runningNow")
+            : job.last_finished
+              ? t("scheduler.lastRun", { time: relativeTime(job.last_finished) })
+              : t("scheduler.neverRun")}
+          {job.last_error ? (
+            <span className="text-red-400"> · {job.last_error}</span>
+          ) : job.last_result ? (
+            <span> · {job.last_result}</span>
+          ) : null}
+        </div>
+      </div>
+      <div className="shrink-0 text-right text-[11px] text-muted tabular-nums">
+        {job.running ? (
+          <span className="text-accent">{t("scheduler.active")}</span>
+        ) : next != null ? (
+          <>
+            <div className="uppercase tracking-wide text-[10px]">{t("scheduler.nextRun")}</div>
+            <div>{fmtCountdown(next)}</div>
+          </>
+        ) : (
+          "—"
+        )}
+      </div>
+    </div>
+  );
+}
+
+function Stat({
+  icon: Icon,
+  label,
+  value,
+  hint,
+  sub,
+}: {
+  icon: typeof Database;
+  label: string;
+  value: string | number;
+  hint?: string;
+  sub?: string;
+}) {
+  return (
+    <div className="glass-card rounded-xl p-3">
+      <div className="flex items-center gap-2 text-muted text-xs">
+        <Icon className="w-4 h-4 shrink-0" />
+        <Tooltip hint={hint ?? ""}>
+          <span className={hint ? "underline decoration-dotted decoration-muted/40 underline-offset-4 cursor-help" : ""}>
+            {label}
+          </span>
+        </Tooltip>
+      </div>
+      <div className="text-xl font-semibold mt-1 tabular-nums">{value}</div>
+      {sub && <div className="text-[11px] text-muted">{sub}</div>}
+    </div>
+  );
+}
+
+export default function Scheduler() {
+  const { t } = useTranslation();
+  const qc = useQueryClient();
+  const q = useLiveQuery<SchedulerStatus>(["scheduler"], api.schedulerStatus, {
+    intervalMs: POLL_MS,
+  });
+  const data = q.data;
+
+  // Tick once a second so the per-job countdowns move between polls.
+  const [, setTick] = useState(0);
+  useEffect(() => {
+    const id = setInterval(() => setTick((n) => n + 1), 1000);
+    return () => clearInterval(id);
+  }, []);
+
+  const pauseResume = useMutation({
+    mutationFn: (paused: boolean) => (paused ? api.resumeSync() : api.pauseSync()),
+    onSuccess: () => qc.invalidateQueries({ queryKey: ["scheduler"] }),
+    onError: () => notify({ level: "error", message: t("scheduler.toggleFailed") }),
+  });
+
+  if (q.isLoading && !data)
+    return <div className="p-8 text-muted">{t("scheduler.loading")}</div>;
+  if (!data)
+    return <div className="p-8 text-muted">{t("common.somethingWrong")}</div>;
+
+  const quotaPct = data.quota.daily_budget
+    ? Math.min(100, Math.round((data.quota.used_today / data.quota.daily_budget) * 100))
+    : 0;
+
+  return (
+    <div className="p-4 max-w-4xl w-full mx-auto space-y-4">
+      {/* Status strip */}
+      <div className="glass rounded-2xl p-4 flex flex-wrap items-center gap-3">
+        <Activity className="w-5 h-5 text-accent shrink-0" />
+        <div className="min-w-0">
+          <div className="font-semibold">{t("scheduler.title")}</div>
+          <div className="text-xs text-muted flex items-center gap-2 flex-wrap">
+            <span className="inline-flex items-center gap-1">
+              <span
+                className={`w-2 h-2 rounded-full ${
+                  data.paused ? "bg-amber-500" : data.running_here ? "bg-emerald-500" : "bg-border"
+                }`}
+              />
+              {data.paused
+                ? t("scheduler.paused")
+                : data.running_here
+                  ? t("scheduler.running")
+                  : t("scheduler.notHere")}
+            </span>
+            {q.isFetching && <span className="text-accent">· {t("scheduler.updating")}</span>}
+          </div>
+        </div>
+        <div className="flex-1" />
+        <Tooltip hint={t("scheduler.pauseHint")}>
+          <button
+            onClick={() => pauseResume.mutate(data.paused)}
+            disabled={pauseResume.isPending}
+            className="glass-card glass-hover flex items-center gap-2 px-3 py-2 rounded-xl text-sm disabled:opacity-50 transition"
+          >
+            {data.paused ? <Play className="w-4 h-4" /> : <Pause className="w-4 h-4" />}
+            {data.paused ? t("scheduler.resume") : t("scheduler.pause")}
+          </button>
+        </Tooltip>
+      </div>
+
+      {!data.running_here && (
+        <div className="flex items-center gap-2 text-sm bg-amber-500/15 border border-amber-500/30 rounded-xl px-3 py-2">
+          <AlertTriangle className="w-4 h-4 text-amber-500 shrink-0" />
+          <span className="text-muted">{t("scheduler.notHereNote")}</span>
+        </div>
+      )}
+
+      {/* Jobs */}
+      <div>
+        <div className="text-xs uppercase tracking-wide text-muted mb-2">{t("scheduler.jobsTitle")}</div>
+        <div className="space-y-1.5">
+          {data.jobs.map((job) => (
+            <JobRow key={job.id} job={job} />
+          ))}
+        </div>
+      </div>
+
+      {/* Queue */}
+      <div>
+        <div className="text-xs uppercase tracking-wide text-muted mb-2">{t("scheduler.queueTitle")}</div>
+        <div className="grid grid-cols-2 sm:grid-cols-3 gap-2">
+          <Stat
+            icon={Database}
+            label={t("scheduler.queue.recentPending")}
+            hint={t("scheduler.queue.recentPendingHint")}
+            value={data.queue.channels_recent_pending.toLocaleString()}
+          />
+          <Stat
+            icon={Database}
+            label={t("scheduler.queue.deepPending")}
+            hint={t("scheduler.queue.deepPendingHint")}
+            value={data.queue.channels_deep_pending.toLocaleString()}
+          />
+          <Stat
+            icon={Clock}
+            label={t("scheduler.queue.enrichPending")}
+            hint={t("scheduler.queue.enrichPendingHint")}
+            value={data.queue.videos_pending_enrich.toLocaleString()}
+          />
+          <Stat
+            icon={Clock}
+            label={t("scheduler.queue.shortsPending")}
+            hint={t("scheduler.queue.shortsPendingHint")}
+            value={data.queue.videos_pending_shorts.toLocaleString()}
+          />
+          <Stat
+            icon={RadioTower}
+            label={t("scheduler.queue.liveRefresh")}
+            hint={t("scheduler.queue.liveRefreshHint")}
+            value={data.queue.videos_live_refresh.toLocaleString()}
+          />
+        </div>
+      </div>
+
+      {/* Quota */}
+      <div>
+        <div className="text-xs uppercase tracking-wide text-muted mb-2">{t("scheduler.quotaTitle")}</div>
+        <div className="glass-card rounded-xl p-4">
+          <div className="flex items-center gap-2 text-sm">
+            <Gauge className="w-4 h-4 text-muted shrink-0" />
+            <span>
+              {t("scheduler.quotaUsed", {
+                used: data.quota.used_today.toLocaleString(),
+                budget: data.quota.daily_budget.toLocaleString(),
+              })}
+            </span>
+            <span className="flex-1" />
+            <span className="text-muted text-xs">
+              {t("scheduler.quotaRemaining", {
+                count: data.quota.remaining_today,
+                formatted: data.quota.remaining_today.toLocaleString(),
+              })}
+            </span>
+          </div>
+          <div className="mt-2 h-2 rounded-full bg-border overflow-hidden">
+            <div
+              className={`h-full rounded-full ${quotaPct > 90 ? "bg-red-500" : "bg-accent"}`}
+              style={{ width: `${quotaPct}%` }}
+            />
+          </div>
+          <div className="text-[11px] text-muted mt-1.5">{t("scheduler.quotaNote")}</div>
+        </div>
+      </div>
+    </div>
+  );
+}

frontend/src/i18n/locales/de/header.json

@@ -3,6 +3,7 @@
   "searchPlaceholder": "Deine Abos durchsuchen…",
   "channelManager": "Kanalverwaltung",
   "usageStats": "Nutzung & Statistik",
+  "scheduler": "Planer",
   "scope": {
     "label": "Feed-Quelle",
     "my": "Meine",
@@ -16,6 +17,7 @@
     "channels": "Kanäle",
     "playlists": "Wiedergabelisten",
     "stats": "Statistik",
+    "scheduler": "Planer",
     "settings": "Einstellungen",
     "about": "Über",
     "signOut": "Abmelden",

frontend/src/i18n/locales/de/scheduler.json

@@ -0,0 +1,46 @@
+{
+  "title": "Hintergrund-Planer",
+  "loading": "Planer wird geladen…",
+  "running": "Läuft",
+  "paused": "Pausiert",
+  "notHere": "Läuft in dieser Instanz nicht",
+  "notHereNote": "Der Planer läuft auf dem Server. Diese Instanz zeigt die gemeinsame Warteschlange und das Kontingent, aber die Live-Job-Aktivität erscheint nur dort, wo der Planer läuft.",
+  "updating": "wird aktualisiert…",
+  "pause": "Pausieren",
+  "resume": "Fortsetzen",
+  "pauseHint": "Die gesamte Hintergrund-Synchronisierung der App pausieren oder fortsetzen (für alle Nutzer).",
+  "toggleFailed": "Der Planer-Status konnte nicht geändert werden",
+  "jobsTitle": "Jobs",
+  "queueTitle": "Wartende Arbeit",
+  "quotaTitle": "Gemeinsames API-Kontingent",
+  "everyMin": "alle {{count}} Min",
+  "runningNow": "Läuft gerade…",
+  "lastRun": "Letzter Lauf {{time}}",
+  "neverRun": "In dieser Sitzung noch nicht gelaufen",
+  "active": "aktiv",
+  "nextRun": "nächster",
+  "quotaUsed": "{{used}} / {{budget}} Einheiten heute verbraucht",
+  "quotaRemaining": "{{formatted}} übrig",
+  "quotaNote": "Gemeinsames YouTube-Data-API-Budget; Reset um Mitternacht US-Pazifik. Backfill tritt zurück, um Spielraum für interaktive Nutzung zu lassen.",
+  "jobs": {
+    "rss_poll": "RSS-Abfrage (neue Uploads)",
+    "enrich": "Anreicherung + Live-Aktualisierung",
+    "backfill": "Backfill (aktuell + ganze Historie)",
+    "autotag": "Automatisches Tagging",
+    "shorts": "Shorts-Klassifizierung",
+    "subscriptions": "Abo-Resync",
+    "playlist_sync": "YouTube-Wiedergabelisten-Sync"
+  },
+  "queue": {
+    "recentPending": "Zu synchronisierende Kanäle",
+    "recentPendingHint": "Kanäle, deren neueste Uploads noch nicht abgerufen wurden.",
+    "deepPending": "Ganze Historie ausstehend",
+    "deepPendingHint": "Für vollständigen Verlauf vorgemerkte Kanäle, die noch nicht fertig sind.",
+    "enrichPending": "Zu anreichernde Videos",
+    "enrichPendingHint": "Videos, die noch auf Details warten (Dauer, Statistiken, Live-/Short-Klassifizierung).",
+    "shortsPending": "Zu klassifizierende Shorts",
+    "shortsPendingHint": "Bereits angereicherte Videos, die noch auf die Shorts-Prüfung warten.",
+    "liveRefresh": "Live zu aktualisieren",
+    "liveRefreshHint": "Live-/bevorstehende Videos (und gerade beendete Streams ohne Dauer), bis sie sich stabilisieren."
+  }
+}

frontend/src/i18n/locales/en/header.json

@@ -3,6 +3,7 @@
   "searchPlaceholder": "Search your subscriptions…",
   "channelManager": "Channel manager",
   "usageStats": "Usage & stats",
+  "scheduler": "Scheduler",
   "scope": {
     "label": "Feed source",
     "my": "Mine",
@@ -16,6 +17,7 @@
     "channels": "Channels",
     "playlists": "Playlists",
     "stats": "Stats",
+    "scheduler": "Scheduler",
     "settings": "Settings",
     "about": "About",
     "signOut": "Sign out",

frontend/src/i18n/locales/en/scheduler.json

@@ -0,0 +1,46 @@
+{
+  "title": "Background scheduler",
+  "loading": "Loading scheduler…",
+  "running": "Running",
+  "paused": "Paused",
+  "notHere": "Not running in this instance",
+  "notHereNote": "The scheduler runs on the server. This instance shows the shared queue and quota, but live job activity appears only where the scheduler runs.",
+  "updating": "updating…",
+  "pause": "Pause",
+  "resume": "Resume",
+  "pauseHint": "Pause or resume all background sync for the whole app (every user).",
+  "toggleFailed": "Couldn't change the scheduler state",
+  "jobsTitle": "Jobs",
+  "queueTitle": "Work queued",
+  "quotaTitle": "Shared API quota",
+  "everyMin": "every {{count}} min",
+  "runningNow": "Running now…",
+  "lastRun": "Last run {{time}}",
+  "neverRun": "Hasn't run yet this session",
+  "active": "active",
+  "nextRun": "next",
+  "quotaUsed": "{{used}} / {{budget}} units used today",
+  "quotaRemaining": "{{formatted}} left",
+  "quotaNote": "Shared YouTube Data API budget; resets at midnight US Pacific. Backfill yields to leave headroom for interactive use.",
+  "jobs": {
+    "rss_poll": "RSS poll (new uploads)",
+    "enrich": "Enrichment + live refresh",
+    "backfill": "Backfill (recent + full history)",
+    "autotag": "Auto-tagging",
+    "shorts": "Shorts classification",
+    "subscriptions": "Subscription resync",
+    "playlist_sync": "YouTube playlist sync"
+  },
+  "queue": {
+    "recentPending": "Channels to sync",
+    "recentPendingHint": "Channels whose recent uploads haven't been fetched yet.",
+    "deepPending": "Full-history pending",
+    "deepPendingHint": "Channels opted into full-history backfill that aren't finished yet.",
+    "enrichPending": "Videos to enrich",
+    "enrichPendingHint": "Videos awaiting details (duration, stats, live/short classification).",
+    "shortsPending": "Shorts to classify",
+    "shortsPendingHint": "Enriched videos still awaiting the Shorts probe.",
+    "liveRefresh": "Live to refresh",
+    "liveRefreshHint": "Live/upcoming videos (and just-ended streams without a duration yet) re-checked until they settle."
+  }
+}

frontend/src/i18n/locales/hu/header.json

@@ -3,6 +3,7 @@
   "searchPlaceholder": "Keresés a feliratkozásaid között…",
   "channelManager": "Csatornakezelő",
   "usageStats": "Használat és statisztika",
+  "scheduler": "Ütemező",
   "scope": {
     "label": "Hírfolyam forrása",
     "my": "Sajátom",
@@ -16,6 +17,7 @@
     "channels": "Csatornák",
     "playlists": "Lejátszási listák",
     "stats": "Statisztika",
+    "scheduler": "Ütemező",
     "settings": "Beállítások",
     "about": "Névjegy",
     "signOut": "Kijelentkezés",

frontend/src/i18n/locales/hu/scheduler.json

@@ -0,0 +1,46 @@
+{
+  "title": "Háttér-ütemező",
+  "loading": "Ütemező betöltése…",
+  "running": "Fut",
+  "paused": "Szüneteltetve",
+  "notHere": "Ebben a példányban nem fut",
+  "notHereNote": "Az ütemező a szerveren fut. Ez a példány a közös sort és kvótát mutatja, de az élő job-aktivitás csak ott látszik, ahol az ütemező fut.",
+  "updating": "frissítés…",
+  "pause": "Szüneteltetés",
+  "resume": "Folytatás",
+  "pauseHint": "A teljes app háttér-szinkronjának szüneteltetése vagy folytatása (minden felhasználóra).",
+  "toggleFailed": "Nem sikerült módosítani az ütemező állapotát",
+  "jobsTitle": "Feladatok",
+  "queueTitle": "Sorban álló munka",
+  "quotaTitle": "Közös API-kvóta",
+  "everyMin": "{{count}} percenként",
+  "runningNow": "Most fut…",
+  "lastRun": "Utolsó futás {{time}}",
+  "neverRun": "Ebben a munkamenetben még nem futott",
+  "active": "aktív",
+  "nextRun": "köv.",
+  "quotaUsed": "{{used}} / {{budget}} egység ma felhasználva",
+  "quotaRemaining": "{{formatted}} maradt",
+  "quotaNote": "Közös YouTube Data API-keret; éjfélkor (US Pacific) nullázódik. A backfill hátrébb sorol, hogy maradjon hely az interaktív használatnak.",
+  "jobs": {
+    "rss_poll": "RSS-lekérdezés (új feltöltések)",
+    "enrich": "Adatdúsítás + élő frissítés",
+    "backfill": "Backfill (friss + teljes előzmény)",
+    "autotag": "Automatikus címkézés",
+    "shorts": "Shorts-besorolás",
+    "subscriptions": "Feliratkozások újraszinkronja",
+    "playlist_sync": "YouTube lejátszási listák szinkronja"
+  },
+  "queue": {
+    "recentPending": "Szinkronra váró csatorna",
+    "recentPendingHint": "Csatornák, amelyek friss feltöltéseit még nem kértük le.",
+    "deepPending": "Teljes előzmény függőben",
+    "deepPendingHint": "Teljes előzményre kijelölt csatornák, amelyek még nincsenek kész.",
+    "enrichPending": "Dúsításra váró videó",
+    "enrichPendingHint": "Videók, amelyek még adatokra várnak (hossz, statisztikák, live/short besorolás).",
+    "shortsPending": "Besorolásra váró Shorts",
+    "shortsPendingHint": "Már dúsított videók, amelyek még a Shorts-próbára várnak.",
+    "liveRefresh": "Frissítendő élő",
+    "liveRefreshHint": "Élő/közelgő videók (és a frissen véget ért, hossz nélküli adások), amíg le nem ülepednek."
+  }
+}

frontend/src/lib/api.ts

@@ -303,6 +303,39 @@ export interface ManagedChannel {
   backfill_done: boolean;
 }
 
+export interface SchedulerJob {
+  id: string;
+  interval_minutes: number;
+  next_run: string | null;
+  running: boolean;
+  status: "ok" | "error" | "skipped" | null;
+  last_started: string | null;
+  last_finished: string | null;
+  last_result: string | null;
+  last_error: string | null;
+}
+
+export interface SchedulerStatus {
+  running_here: boolean;
+  enabled: boolean;
+  paused: boolean;
+  jobs: SchedulerJob[];
+  queue: {
+    channels_recent_pending: number;
+    channels_deep_pending: number;
+    deep_eta_seconds: number;
+    videos_pending_enrich: number;
+    videos_pending_shorts: number;
+    videos_live_refresh: number;
+  };
+  quota: {
+    used_today: number;
+    remaining_today: number;
+    daily_budget: number;
+    backfill_reserve: number;
+  };
+}
+
 export interface Account {
   id: number;
   email: string;
@@ -400,6 +433,7 @@ export const api = {
   // --- quota usage ---
   myUsage: (): Promise<MyUsage> => req("/api/quota/my-usage"),
   adminQuota: (days = 30): Promise<AdminQuota> => req(`/api/quota/admin?days=${days}`),
+  schedulerStatus: (): Promise<SchedulerStatus> => req("/api/admin/scheduler"),
 
   // --- onboarding / admin ---
   requestAccess: (email: string): Promise<{ status: string }> =>

frontend/src/lib/urlState.ts

@@ -78,11 +78,15 @@ export function hasFilterParams(params: URLSearchParams): boolean {
   return KEYS.some((k) => params.has(k));
 }
 
-export type Page = "feed" | "channels" | "stats" | "playlists" | "settings";
+export type Page = "feed" | "channels" | "stats" | "playlists" | "settings" | "scheduler";
 
 export function readPage(): Page {
   const p = new URLSearchParams(window.location.search).get("page");
-  return p === "channels" || p === "stats" || p === "playlists" || p === "settings"
+  return p === "channels" ||
+    p === "stats" ||
+    p === "playlists" ||
+    p === "settings" ||
+    p === "scheduler"
     ? p
     : "feed";
 }

frontend/src/lib/useLiveQuery.ts

@@ -0,0 +1,22 @@
+import { useQuery, type QueryKey } from "@tanstack/react-query";
+
+// Reusable "live" polling query: a thin wrapper over react-query that refetches on an
+// interval and — by leaving refetchIntervalInBackground at its default false — pauses while
+// the tab is unfocused, so it doesn't poll a server nobody's watching. This is the shared
+// live-progress mechanism: the Scheduler dashboard uses it now; the notification bell and the
+// future yt-dlp job queue reuse it rather than each re-implementing polling.
+export function useLiveQuery<T>(
+  key: QueryKey,
+  queryFn: () => Promise<T>,
+  opts: { intervalMs?: number; enabled?: boolean } = {}
+) {
+  const { intervalMs = 4000, enabled = true } = opts;
+  return useQuery({
+    queryKey: key,
+    queryFn,
+    enabled,
+    refetchInterval: enabled ? intervalMs : false,
+    refetchIntervalInBackground: false,
+    staleTime: 0,
+  });
+}