fix(admin-ui): Plex library toggle inversion + Purge-discovery confirm (+ cleanups)

Bugs:
- ConfigPanel (CB1): unchecking a Plex library from the "all" (empty) state made
  that library the ONLY selected one instead of all-except-it, because the toggle
  ADDED the key to an empty list. Expand "all" to the explicit section set before
  toggling. E2E-verified: uncheck from all → all-except-one.
- Scheduler (SB1): "Purge discovery" bulk-deleted search videos/videos/channels
  immediately with no confirm (every AdminUsers destructive action uses useConfirm).
  Wrapped in a danger useConfirm dialog (+ trilingual purgeConfirmTitle key).
  E2E-verified: dialog appears, Cancel aborts.

Cleanups (behavior-neutral):
- Register LS.configTab; ConfigPanel uses it instead of the bare "siftlode.configTab".
- ConfigPanel + SettingsPanel import SaveState from ui/DraftSaveBar instead of
  redeclaring the union (PrefsSaveState is now an alias).

tsc green, re-review clean, localdev boots.

frontend/src/components/ConfigPanel.tsx

@@ -7,7 +7,8 @@ import { notify } from "../lib/notifications";
 import Tooltip from "./Tooltip";
 import Tabs, { usePersistedTab } from "./Tabs";
 import { Switch } from "./ui/form";
-import { DraftSaveBar } from "./ui/DraftSaveBar";
+import { DraftSaveBar, type SaveState } from "./ui/DraftSaveBar";
+import { LS } from "../lib/storage";
 
 // Admin Configuration page: edit DB-overridable operational settings (registry-driven from the
 // backend — adding a key there makes it appear here automatically). Edits are drafted and
@@ -15,7 +16,6 @@ import { DraftSaveBar } from "./ui/DraftSaveBar";
 // the server until Save. Group order is fixed where known so logically related settings (e.g.
 // Email/SMTP) stay together.
 const GROUP_ORDER = ["access", "email", "youtube", "google", "quota", "backfill", "shorts", "batch", "downloads", "plex"];
-type SaveState = "idle" | "saving" | "saved" | "error";
 
 export default function ConfigPanel() {
   const { t } = useTranslation();
@@ -40,7 +40,7 @@ export default function ConfigPanel() {
   const [saveState, setSaveState] = useState<SaveState>("idle");
   // One tab per config group (persisted). Called before the loading guard so hook order is
   // stable; the active id is clamped to a real group at render time once data has loaded.
-  const [tab, setTab] = usePersistedTab("siftlode.configTab");
+  const [tab, setTab] = usePersistedTab(LS.configTab);
 
   // Re-seed the draft whenever the server data changes (initial load + after a save/reset).
   useEffect(() => {
@@ -110,9 +110,14 @@ export default function ConfigPanel() {
   });
   const plexLibs = (draft["plex_libraries"] ?? "").split(",").map((s) => s.trim()).filter(Boolean);
   const togglePlexLib = (key: string) => {
-    const next = plexLibs.includes(key)
-      ? plexLibs.filter((k) => k !== key)
-      : [...plexLibs, key];
+    // An empty list means "all libraries" — every box renders checked. Unchecking one from that
+    // state must select all-except-this, so expand "all" to the explicit section set first;
+    // otherwise the toggle would ADD the key and leave it as the ONLY selected library.
+    const allKeys = plexResult?.sections?.map((s) => s.key) ?? [];
+    const current = plexLibs.length === 0 ? allKeys : plexLibs;
+    const next = current.includes(key)
+      ? current.filter((k) => k !== key)
+      : [...current, key];
     setDraft((d) => ({ ...d, plex_libraries: next.join(",") }));
   };
 

frontend/src/components/Scheduler.tsx

@@ -18,6 +18,7 @@ import {
 } from "lucide-react";
 import { api, type SchedulerJob, type SchedulerStatus } from "../lib/api";
 import { useLiveQuery } from "../lib/useLiveQuery";
+import { useConfirm } from "./ConfirmProvider";
 import { relativeTime } from "../lib/format";
 import { notify } from "../lib/notifications";
 import Tooltip from "./Tooltip";
@@ -309,6 +310,7 @@ function Stat({
 export default function Scheduler() {
   const { t } = useTranslation();
   const qc = useQueryClient();
+  const confirm = useConfirm();
   // Poll faster while any job is running so live progress is smooth, then ease back when
   // idle. Derived from the freshest data by react-query itself (see useLiveQuery).
   const q = useLiveQuery<SchedulerStatus>(["scheduler"], api.schedulerStatus, {
@@ -411,7 +413,15 @@ export default function Scheduler() {
         </Tooltip>
         <Tooltip hint={t("scheduler.purgeDiscoveryHint")}>
           <button
-            onClick={() => purgeMut.mutate()}
+            onClick={async () => {
+              const ok = await confirm({
+                title: t("scheduler.purgeConfirmTitle"),
+                message: t("scheduler.purgeDiscoveryHint"),
+                confirmLabel: t("scheduler.purgeDiscovery"),
+                danger: true,
+              });
+              if (ok) purgeMut.mutate();
+            }}
             disabled={purgeMut.isPending}
             className="glass-card glass-hover flex items-center gap-2 px-3 py-2 rounded-xl text-sm disabled:opacity-50 transition"
           >

frontend/src/components/SettingsPanel.tsx

@@ -9,14 +9,14 @@ import Avatar from "./Avatar";
 import { notify, type NotifSettings } from "../lib/notifications";
 import Tooltip from "./Tooltip";
 import { Section, SettingRow, Switch } from "./ui/form";
-import { DraftSaveBar } from "./ui/DraftSaveBar";
+import { DraftSaveBar, type SaveState } from "./ui/DraftSaveBar";
 import { useConfirm } from "./ConfirmProvider";
 
 // The Settings page edits server-persisted preferences as a draft: changes apply locally
 // for instant preview but reach the server only on an explicit Save (or revert on Discard).
 // App owns the draft + baseline (so the leave-the-page guard can see it); this controller is
 // how the panel reads/writes it. See App.tsx.
-export type PrefsSaveState = "idle" | "saving" | "saved" | "error";
+export type PrefsSaveState = SaveState;
 export interface PrefsController {
   theme: ThemePrefs;
   setTheme: (t: ThemePrefs) => void;

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

@@ -103,5 +103,6 @@
   },
   "purgeDiscovery": "Entdeckung leeren",
   "purgeDiscoveryHint": "Alle nicht behaltenen Entdeckungsinhalte jetzt entfernen (von niemandem angesehene/gespeicherte Suchergebnisse und erkundete, nicht abonnierte Kanäle) — ohne Karenzzeit.",
+  "purgeConfirmTitle": "Entdeckungsinhalte löschen?",
   "purgedDiscovery": "{{count}} Entdeckungselemente entfernt"
 }

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

@@ -103,5 +103,6 @@
   },
   "purgeDiscovery": "Purge discovery",
   "purgeDiscoveryHint": "Remove all un-kept discovery content now (search results nobody watched/saved, and explored-but-unsubscribed channels) — ignoring the grace period.",
+  "purgeConfirmTitle": "Purge discovery content?",
   "purgedDiscovery": "Removed {{count}} discovery items"
 }

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

@@ -103,5 +103,6 @@
   },
   "purgeDiscovery": "Felfedezés ürítése",
   "purgeDiscoveryHint": "Most eltávolítja az összes meg nem tartott felfedezés-tartalmat (senki által meg nem nézett/mentett keresési találatok és felfedezett, de nem követett csatornák) — a türelmi időt figyelmen kívül hagyva.",
+  "purgeConfirmTitle": "Felfedezés-tartalom törlése?",
   "purgedDiscovery": "{{count}} felfedezés-elem eltávolítva"
 }

frontend/src/lib/storage.ts

@@ -19,6 +19,7 @@ export const LS = {
   channelsTable: "siftlode.channelsTable",
   channelDiscoveryTable: "siftlode.channelDiscoveryTable",
   settingsTab: "siftlode.settingsTab",
+  configTab: "siftlode.configTab",
   statsTab: "siftlode.statsTab",
   adminUsersTab: "siftlode.adminUsersTab",
   navCollapsed: "siftlode.navCollapsed",