fix: improve route direction logic to align with backend derivation rules

apps/edr-freight-web/portal/src/pages/bookings/new-booking-form/schema.ts

@@ -288,22 +288,33 @@ export interface WagonConfig {
   type: "20ft" | "40ft";
 }
 
+/**
+ * Derive the trade direction from the origin/destination yard countries.
+ *
+ * Mirrors the backend's `deriveTradeDirection` exactly so the value the portal
+ * sends always matches what the API re-derives (the API rejects mismatches):
+ *   - origin in Djibouti                      → IMPORT
+ *   - destination in Djibouti (origin not)    → EXPORT
+ *   - everything else (e.g. Ethiopia↔Ethiopia)→ DOMESTIC
+ *
+ * Returns null only while a yard is still unselected, so the UI can wait.
+ */
 export function getRouteDirection(
   origin: Freight.BookingReferenceYard | null | undefined,
   dest: Freight.BookingReferenceYard | null | undefined,
 ): Freight.ScheduleTradeDirection | null {
   if (!origin || !dest) return null;
-  if (origin.country === "Ethiopia" && dest.country === "Ethiopia") {
+
-    return "DOMESTIC";
+  const originCountry = origin.country?.trim();
-  }
+  const destCountry = dest.country?.trim();
-  if (origin.country === "Ethiopia" && dest.country === "Djibouti") {
+
-    return "EXPORT";
+  if (originCountry === "Djibouti") {
-  }
-  if (origin.country === "Djibouti" && dest.country === "Ethiopia") {
     return "IMPORT";
   }
-
+  if (destCountry === "Djibouti" && originCountry !== "Djibouti") {
-  return null;
+    return "EXPORT";
+  }
+  return "DOMESTIC";
 }
 
 export function calcWagons(containers: ContainerConfig[]) {