feat(ui-common): shared currency formatting + DJF in CurrencySelector

New lib/currency.ts is the single source of truth for currency
display across both freight web apps: symbol, name and decimals per
code (DJF is zero-decimal by convention, unlike ETB/USD). Portal's own
currency lib and backoffice's ad-hoc formatters are rewired onto this
in the next two commits instead of each guessing decimals.

CurrencySelector gets an allowDjf prop mirroring the existing allowUsd
gate, so import-shipment currency pickers can offer DJF the same way
they offer USD.

Claude-Session: https://claude.ai/code/session_01CZy77vCWhka3pnmVF9NDkL

packages/ui-common/src/components/CurrencySelector/CurrencySelector.tsx

@@ -1,10 +1,12 @@
 import { Box, Text } from "@mantine/core";
 import { Check } from "lucide-react";
 
+import type { SupportedCurrency } from "../../lib/currency";
+
 export interface CurrencySelectorProps {
   /** Selected currency code, or "" when none picked yet. */
   value: string;
-  onChange: (currency: "USD" | "ETB") => void;
+  onChange: (currency: SupportedCurrency) => void;
   disabled?: boolean;
   /** Validation error shown under the cards. */
   error?: string;
@@ -14,6 +16,12 @@ export interface CurrencySelectorProps {
    * USD is settled by bank transfer, never through the online gateway.
    */
   allowUsd?: boolean;
+  /**
+   * Offer DJF alongside ETB (and USD, if also allowed). Same import-only
+   * gating as `allowUsd` — DJF is settled both online (WAAFI / CAC Bank) and
+   * by bank transfer.
+   */
+  allowDjf?: boolean;
 }
 
 const ETB_OPTION = {
@@ -30,6 +38,13 @@ const USD_OPTION = {
   hint: "Paid by bank transfer — send the slip to Finance",
 } as const;
 
+const DJF_OPTION = {
+  code: "DJF",
+  symbol: "Fdj",
+  name: "Djibouti Franc",
+  hint: "Pay online, or by bank transfer — send the slip to Finance",
+} as const;
+
 /**
  * Card-style USD/ETB billing-currency picker. Renders unselected when `value`
  * is "" so a required choice never looks pre-made.
@@ -40,8 +55,13 @@ export function CurrencySelector({
   disabled = false,
   error,
   allowUsd = false,
+  allowDjf = false,
 }: CurrencySelectorProps) {
-  const options = allowUsd ? [ETB_OPTION, USD_OPTION] : [ETB_OPTION];
+  const options = [
+    ETB_OPTION,
+    ...(allowUsd ? [USD_OPTION] : []),
+    ...(allowDjf ? [DJF_OPTION] : []),
+  ];
   return (
     <Box>
       <Box

packages/ui-common/src/index.ts

@@ -80,3 +80,12 @@ export type {
   BookingWindowStateInput,
   BookingWindowUiState,
 } from "./lib/booking-window-display";
+
+export {
+  CURRENCY_META,
+  CURRENCY_CODES,
+  currencyDecimals,
+  currencySymbol,
+  formatCurrency,
+} from "./lib/currency";
+export type { SupportedCurrency } from "./lib/currency";

packages/ui-common/src/lib/currency.ts

@@ -0,0 +1,43 @@
+/**
+ * The currency codes the freight apps support, and how each one displays —
+ * symbol, full name, decimal places. USD/ETB are conventional 2-decimal
+ * currencies; DJF (Djibouti Franc) is a zero-decimal currency by convention.
+ *
+ * Single source of truth for currency display across both freight web apps —
+ * import this instead of re-declaring a symbol map or a decimals rule.
+ */
+export const CURRENCY_META = {
+  ETB: { symbol: "Br", name: "Ethiopian Birr", decimals: 2 },
+  USD: { symbol: "$", name: "US Dollar", decimals: 2 },
+  DJF: { symbol: "Fdj", name: "Djibouti Franc", decimals: 0 },
+} as const;
+
+export type SupportedCurrency = keyof typeof CURRENCY_META;
+
+export const CURRENCY_CODES = Object.keys(CURRENCY_META) as SupportedCurrency[];
+
+/** Decimal places to render an amount in `code` with. Defaults to 2 for an unknown code. */
+export function currencyDecimals(code?: string | null): number {
+  const meta = code ? CURRENCY_META[code as SupportedCurrency] : undefined;
+  return meta?.decimals ?? 2;
+}
+
+/** Display symbol for `code`. Falls back to printing the raw code. */
+export function currencySymbol(code?: string | null): string {
+  const meta = code ? CURRENCY_META[code as SupportedCurrency] : undefined;
+  return meta?.symbol ?? code ?? "";
+}
+
+/**
+ * Format a money amount with its currency symbol, e.g. `Br 12,500.00` or
+ * `Fdj 2,194,318`. Unknown currency codes fall back to printing the raw code
+ * with 2 decimals.
+ */
+export function formatCurrency(amount: number, currency?: string | null): string {
+  const symbol = currencySymbol(currency);
+  const decimals = currencyDecimals(currency);
+  return `${symbol} ${Number(amount ?? 0).toLocaleString(undefined, {
+    minimumFractionDigits: decimals,
+    maximumFractionDigits: decimals,
+  })}`;
+}