fix(filters): honor a date filter's own operator, not always "between"

DateBody always initialized its op state to DEFAULT_OP.date ("between"),
ignoring a def's `operators` restriction. A single-operator exact-date
filter (e.g. `operators: ["before"]`) opened on the range UI with no way
off it, since OperatorSelect hides itself when there's only one choice.
Default to the def's first allowed operator instead.

apps/edr-freight-web/backoffice/src/components/filters/bodies/DateBody.tsx

@@ -15,7 +15,11 @@ import type { FilterBodyProps } from "./TextBody";
 // i18n.language !== "en" branch here when this body is first wired into a
 // record-management page (Phase 4 of the filter-bar rollout).
 export function DateBody({ def, value, onChange, onClose }: FilterBodyProps<DateFilterDef>) {
-  const [op, setOp] = useState<Operator>(value?.op ?? DEFAULT_OP.date);
+  // DEFAULT_OP.date is always "between" — a def restricted to a single
+  // non-default operator (e.g. `operators: ["before"]` for an exact-date
+  // filter) would otherwise open on the range UI with no way to switch off
+  // it, since OperatorSelect hides itself when there's only one choice.
+  const [op, setOp] = useState<Operator>(value?.op ?? def.operators?.[0] ?? DEFAULT_OP.date);
   // Mantine 9's date inputs speak `YYYY-MM-DD` strings, not Date objects.
   const [from, setFrom] = useState<string | null>(value?.v[0]?.slice(0, 10) ?? null);
   const [to, setTo] = useState<string | null>(value?.v[1]?.slice(0, 10) ?? null);