feat(freight-api): add DJF as a supported currency

Adds DJF to freight.payments_currency_enum (migration 3860000000000,
alone in its own migration per Postgres's ADD VALUE-in-a-transaction
restriction) and to manual_payment_settings (djf_enabled column,
migration 3870000000000, default true).

Replaces the binary ETB/USD assumptions that would have silently
mispriced or discarded a DJF booking:
- booking-pricing / contract-pricing: usdToEtb scalar -> a rate table
  keyed by source currency (ExchangeService.getRateTable), so a
  contract-frozen rate converts into whatever currency the booking is
  paid in instead of being dropped when neither leg is ETB or USD.
- warehouse-fee / booking-wagon-cancellation: normalizeCurrency no
  longer coerces anything non-ETB to USD.
- additional-charge: convertAmount no longer bails out for a currency
  that isn't literally ETB or USD.
- manual-payment-settings: isEnabled/enabledCurrencies cover DJF.

Widens the three @IsIn(['ETB','USD']) DTO validators, and adds DJF to
the export/report currency filter option lists.

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

apps/edr-freight-api/src/modules/payment-settings/entities/manual-payment-setting.entity.ts

@@ -20,6 +20,10 @@ export class ManualPaymentSetting extends BaseEntity {
   @Column({ name: "usd_enabled", type: "boolean", default: true })
   usdEnabled!: boolean;
 
+  /** Manual settlement allowed for DJF invoices. */
+  @Column({ name: "djf_enabled", type: "boolean", default: true })
+  djfEnabled!: boolean;
+
   /** IAM user id of the last operator to change either toggle. */
   @Column({ name: "updated_by_id", type: "uuid", nullable: true })
   updatedById?: string | null;