[offers][feat] add currency formatter

apps/portal/src/utils/offers/currency/index.tsx

@@ -0,0 +1,14 @@
+import type { Money } from '~/components/offers/types';
+
+export function convertCurrencyToString({ currency, value }: Money) {
+  if (!value) {
+    return '-';
+  }
+  const formatter = new Intl.NumberFormat('en-US', {
+    currency,
+    maximumFractionDigits: 0, // (this suffices for whole numbers, but will print 2500.10 as $2,500.1)
+    minimumFractionDigits: 0, // (causes 2500.99 to be printed as $2,501)
+    style: 'currency',
+  });
+  return `${formatter.format(10000)}`; /* $2,500.00 */
+}