DATE_CALENDAR
const DATE_CALENDAR: CalendarBackend;Defined in: packages/engine/src/calendar/DateCalendar.ts:128
The one Date backend, shared by every engine that configures no other.
Stateless, so sharing is safe: it holds no zone of its own and reads the
process’s. It is also what the sites with no engine in hand use (the
normaliser rules that fuse a literal, days in <period>, the stocks and
historical-currency date phrases, and formatValue), which is why an
engine’s own backend is the default here rather than a second copy.