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/components/ui/DataTable.tsx

@@ -132,7 +132,8 @@ export default function DataTable<T>({
   // the hidden-filter cue leaves those out, it would name them twice.
   surfacedFilters?: string[];
 }) {
-  const { t } = useTranslation();
+  const { t, i18n } = useTranslation();
+  const lang = i18n.language;
   const initial = loadPersist(persistKey);
   // Sort is controlled when the caller passes onSortChange (it then owns/persists it); otherwise
   // the table keeps its own, seeded from and saved to persistKey.
@@ -212,7 +213,7 @@ export default function DataTable<T>({
     setPage(0);
   }, [resetFiltersToken, commitFilters]);
 
-  const sorted = sortRows(filterRows(rows, columns, filters), columns, sort);
+  const sorted = sortRows(filterRows(rows, columns, filters), columns, sort, lang);
 
   // size <= 0 means "All" — one page with every row.
   const allRows = size <= 0;