fix(i18n): numbers, units, dates and order in the UI language, and after a switch (E30 S3)

Every locale formatter takes the language as an argument. Under the React
Compiler a formatter that read the i18n singleton was memoized on its other
arguments, so a card kept "2 hr 4 min" after a switch to Hungarian; plexLang()
had the same flaw and left Plex queries in the old language. Components now
take the language from useTranslation, and the signature makes forgetting it
a type error.

- ratings, file sizes, stream stats: the language's decimal mark ("8,3")
- view and subscriber counts compact in the language ("1,2 E")
- seconds as the language's unit ("6 mp") in the sliders and the stats
- a person's birth and death dates as dates, not ISO strings
- A-Z lists by the shown name in the language's alphabet (compareText),
  the tag catalog re-sorted by its translated names
- lint local/locale-format (was date-format) also refuses Intl.NumberFormat
  outside lib/format.ts, localeCompare, and a component reading the language
  off the i18n singleton

frontend/src/lib/plexPlayerHooks.ts

@@ -17,7 +17,7 @@ import {
 } from "./fullscreen";
 import { api, type PlexItemDetail, type PlexMarker } from "./api";
 import { qk } from "./queryKeys";
-import { plexLang } from "../i18n";
+import i18n, { plexLang } from "../i18n";
 import { type PlexPlayerPrefs } from "./plexPlayerPrefs";
 import { PLEX_SCALE, normalizeVolumeIn, stepVolumeIn } from "./playerVolume";
 
@@ -264,7 +264,7 @@ export function usePlexProgress(opts: {
     // checkpoint (the resume point when leaving).
     const settle = () => {
       // Match the language-keyed detail query (E5 S6) so the optimistic resume patch lands.
-      const key = qk.plexItem(id, plexLang());
+      const key = qk.plexItem(id, plexLang(i18n.language));
       if (finished) {
         // A refused finish claims nothing: the server has the item unwatched at the position the
         // rollback restored, and the catch below has already dropped this entry, so the next open
@@ -311,7 +311,7 @@ export function usePlexProgress(opts: {
         // `settle` may already have patched the detail to watched / 0 on the way out. Dropping that
         // entry rather than invalidating it: an invalidated query with no observer keeps serving its
         // stale data, and this one is a lie — no data is better, the next open fetches the truth.
-        qc.removeQueries({ queryKey: qk.plexItem(id, plexLang()) });
+        qc.removeQueries({ queryKey: qk.plexItem(id, plexLang(i18n.language)) });
       });
     };
     return () => {