add per-container handling options for hazardous, reefer, and return services

- Introduced new boolean fields (isHazardous, isReefer, isReturn) in UnitDraft and related interfaces to allow individual container handling options.
- Updated emptyUnit function to initialize these new fields.
- Modified GlCreateBookingForm to handle and display these options for each container.
- Adjusted calculations for hazardous, reefer, and return quantities based on the new handling options.
- Updated the schema for container units and booking container lines to include handling options.
- Added migration to support the new return flag in the database.
- Enhanced various components to reflect gross weight calculations, ensuring consistency across the application.

apps/edr-freight-api/src/migrations/2370000000000-AddContainerUnitReturnFlag.ts

@@ -0,0 +1,28 @@
+import { MigrationInterface, QueryRunner } from 'typeorm';
+
+/**
+ * Per-container handling opt-in: each physical container can now be marked
+ * hazardous / reefer / with-return individually, next to its VGM. The hazardous
+ * and reefer flags already existed on the unit row; only the return leg was
+ * missing, so a booking of 20 containers with 10 returning empty can bill the
+ * WITH_RETURN surcharge on 10 instead of all 20.
+ *
+ * Backfill: existing rows keep false. The line-level counts
+ * (booking_container.return_quantity etc.) stay authoritative for bookings made
+ * before this change — the rule engine falls back to them when no unit is flagged.
+ */
+export class AddContainerUnitReturnFlag2370000000000 implements MigrationInterface {
+  name = 'AddContainerUnitReturnFlag2370000000000';
+
+  public async up(queryRunner: QueryRunner): Promise<void> {
+    await queryRunner.query(
+      `ALTER TABLE "freight"."booking_container_units" ADD COLUMN IF NOT EXISTS "is_return" boolean NOT NULL DEFAULT false`,
+    );
+  }
+
+  public async down(queryRunner: QueryRunner): Promise<void> {
+    await queryRunner.query(
+      `ALTER TABLE "freight"."booking_container_units" DROP COLUMN IF EXISTS "is_return"`,
+    );
+  }
+}