style(frontend): Prettier config + one-time repo-wide format pass

Prettier 3 (pinned), printWidth 100, double quotes — chosen to match the existing
hand-formatting and minimise reflow. This commit is ONLY the mechanical format pass
(`prettier --write`) plus the config/ignore/scripts, isolated so it never pollutes a
feature diff. Verified behaviour-neutral: typecheck, eslint (0 errors), and vitest
all green before and after. See .git-blame-ignore-revs — `git blame` skips this sha.

frontend/src/components/PlexSidebar.tsx

@@ -70,18 +70,19 @@ function MatchToggle({
   );
 }
 
-export default function PlexSidebar({
-  layout,
-  setLayout,
-  collapsed,
-  onToggleCollapse,
-}: Props) {
+export default function PlexSidebar({ layout, setLayout, collapsed, onToggleCollapse }: Props) {
   const { t } = useTranslation();
   // Scope / watch-state / sort / expanded filters live in PlexProvider (shared with PlexBrowse and
   // the header search box); this rail is the primary editor of them. Opening a playlist is a
   // hand-off to PlexBrowse via the shared `playlistOpen` slot.
   const { scope, show, sort, filters } = usePlex();
-  const { setScope, setShow, setSort, setFilters, setPlaylistOpen: onOpenPlaylist } = usePlexActions();
+  const {
+    setScope,
+    setShow,
+    setSort,
+    setFilters,
+    setPlaylistOpen: onOpenPlaylist,
+  } = usePlexActions();
   const collFade = useScrollFade();
   const playlistsQ = useQuery({ queryKey: ["plex-playlists"], queryFn: () => api.plexPlaylists() });
   const [newPlaylist, setNewPlaylist] = useState("");
@@ -132,7 +133,8 @@ export default function PlexSidebar({
   const durBucketKey = DURATION_BUCKETS.find(
     (b) => (filters.durationMin ?? null) === b.min && (filters.durationMax ?? null) === b.max,
   )?.key;
-  const peopleActive = filters.directors.length + filters.actors.length + filters.studios.length > 0;
+  const peopleActive =
+    filters.directors.length + filters.actors.length + filters.studios.length > 0;
 
   // Group bodies (no title — the PanelGroup card supplies it). Only available groups are pushed,
   // so facet-gated / scope-gated sections drop out cleanly; PanelGroups orders them by the saved
@@ -226,7 +228,11 @@ export default function PlexSidebar({
           </ChipRow>
           <div className="mt-1.5 flex gap-1">
             {(["asc", "desc"] as const).map((d) => (
-              <Chip key={d} active={(filters.sortDir ?? "asc") === d} onClick={() => patch({ sortDir: d })}>
+              <Chip
+                key={d}
+                active={(filters.sortDir ?? "asc") === d}
+                onClick={() => patch({ sortDir: d })}
+              >
                 {t(`plex.filter.dir.${d}`)}
               </Chip>
             ))}
@@ -310,7 +316,9 @@ export default function PlexSidebar({
               </button>
             ))}
             {collections.length === 0 && (
-              <span className="px-2 py-1 text-xs text-muted">{t("plex.filter.collectionEmpty")}</span>
+              <span className="px-2 py-1 text-xs text-muted">
+                {t("plex.filter.collectionEmpty")}
+              </span>
             )}
           </div>
         </div>
@@ -388,7 +396,9 @@ export default function PlexSidebar({
             body: (
               <ChipRow>
                 <Chip
-                  active={!durBucketKey && filters.durationMin == null && filters.durationMax == null}
+                  active={
+                    !durBucketKey && filters.durationMin == null && filters.durationMax == null
+                  }
                   onClick={() => patch({ durationMin: null, durationMax: null })}
                 >
                   {t("plex.filter.any")}
@@ -416,7 +426,11 @@ export default function PlexSidebar({
             {t("plex.filter.any")}
           </Chip>
           {ADDED_OPTS.map((a) => (
-            <Chip key={a} active={filters.addedWithin === a} onClick={() => patch({ addedWithin: a })}>
+            <Chip
+              key={a}
+              active={filters.addedWithin === a}
+              onClick={() => patch({ addedWithin: a })}
+            >
               {t(`plex.filter.addedOpt.${a}`)}
             </Chip>
           ))}
@@ -434,7 +448,9 @@ export default function PlexSidebar({
                   <Chip
                     key={c.value}
                     active={filters.contentRatings.includes(c.value)}
-                    onClick={() => patch({ contentRatings: toggleIn(filters.contentRatings, c.value) })}
+                    onClick={() =>
+                      patch({ contentRatings: toggleIn(filters.contentRatings, c.value) })
+                    }
                   >
                     {c.value}
                   </Chip>