feat(plex): sort direction, genre any/all, multi-person filters; fix back-nav + player stop

UAT follow-ups on the Plex filter epic:
- Sort now has an asc/desc toggle (sort_dir), applied to any sort field.
- Genre multi-select gains an Any/All mode (genre_mode: OR vs AND containment).
- Director/actor/studio become multi-value: people AND (titles featuring all selected),
  studios OR; clicking them on the info page stacks (unions) instead of replacing, and
  the sidebar shows each as a removable 'Active' chip.
- fix(history): clicking a metadata filter on the info page now pushes a fresh grid
  entry instead of history.back(), so browser Back returns to the info page rather than
  leaving the Plex module.
- fix(player): fully tear down the <video> + hls on unmount and guard late play() calls,
  so backing out of a just-started video no longer leaves audio playing in the background.
i18n en/hu/de (match any/all, sort direction).

frontend/src/components/PlexSidebar.tsx

@@ -155,7 +155,7 @@ export default function PlexSidebar({
         </Section>
       )}
 
-      {/* Sort */}
+      {/* Sort + direction */}
       <Section label={t("plex.filter.sort")}>
         <ChipRow>
           {sorts.map((s) => (
@@ -164,24 +164,43 @@ export default function PlexSidebar({
             </Chip>
           ))}
         </ChipRow>
+        <div className="mt-1.5 flex gap-1">
+          {(["desc", "asc"] as const).map((d) => (
+            <Chip key={d} active={(filters.sortDir ?? "desc") === d} onClick={() => patch({ sortDir: d })}>
+              {t(`plex.filter.dir.${d}`)}
+            </Chip>
+          ))}
+        </div>
       </Section>
 
       {/* Metadata filters (movie libraries only) */}
       {isMovieLib && (
         <>
-          {/* Active people / studio — set by clicking the info page. */}
-          {(filters.director || filters.actor || filters.studio) && (
+          {/* Active people / studios — set by clicking the info page (stackable). */}
+          {filters.directors.length + filters.actors.length + filters.studios.length > 0 && (
             <Section label={t("plex.filter.active")}>
               <div className="flex flex-wrap gap-1.5">
-                {filters.director && (
-                  <RemovableChip label={filters.director} onRemove={() => patch({ director: null })} />
-                )}
-                {filters.actor && (
-                  <RemovableChip label={filters.actor} onRemove={() => patch({ actor: null })} />
-                )}
-                {filters.studio && (
-                  <RemovableChip label={filters.studio} onRemove={() => patch({ studio: null })} />
-                )}
+                {filters.directors.map((d) => (
+                  <RemovableChip
+                    key={`d:${d}`}
+                    label={d}
+                    onRemove={() => patch({ directors: filters.directors.filter((x) => x !== d) })}
+                  />
+                ))}
+                {filters.actors.map((a) => (
+                  <RemovableChip
+                    key={`a:${a}`}
+                    label={a}
+                    onRemove={() => patch({ actors: filters.actors.filter((x) => x !== a) })}
+                  />
+                ))}
+                {filters.studios.map((s) => (
+                  <RemovableChip
+                    key={`s:${s}`}
+                    label={s}
+                    onRemove={() => patch({ studios: filters.studios.filter((x) => x !== s) })}
+                  />
+                ))}
               </div>
             </Section>
           )}
@@ -200,9 +219,26 @@ export default function PlexSidebar({
             </ChipRow>
           </Section>
 
-          {/* Genres (from facets) */}
+          {/* Genres (from facets) + Any/All when more than one is picked */}
           {facets && facets.genres.length > 0 && (
             <Section label={t("plex.filter.genre")}>
+              {filters.genres.length > 1 && (
+                <div className="mb-1.5 inline-flex overflow-hidden rounded-lg border border-border text-[11px]">
+                  {(["any", "all"] as const).map((m) => (
+                    <button
+                      key={m}
+                      onClick={() => patch({ genreMode: m })}
+                      className={`px-2 py-0.5 transition ${
+                        (filters.genreMode ?? "any") === m
+                          ? "bg-accent text-accent-fg"
+                          : "text-muted hover:bg-surface"
+                      }`}
+                    >
+                      {t(`plex.filter.match.${m}`)}
+                    </button>
+                  ))}
+                </div>
+              )}
               <ChipRow>
                 {facets.genres.map((g) => (
                   <Chip