fix(operations): last-mile assign until load fully trucked + 40ft cap

Assign was gated on any truck assigned, blocking multi-truck
deliveries. Gate on remaining containers (or bulk tonnage) instead, show
covered/total in the modal, cap a 40ft container to one truck with no
size mixing (mirrors assertTruckLoad), and lock arrived/departed rows.

apps/edr-freight-api/src/modules/train-scheduling/facility-handling.service.ts

@@ -67,6 +67,21 @@ export class FacilityHandlingService {
         inventoryId = inv?.id ?? null;
       }
 
+      // The handed-over weight: the booking's declared VGM, else what its
+      // containers actually carry. A GRN without a weight is not a receipt.
+      let weightTons = Number(booking.cargoTotalWeightVgm) || null;
+      if (!weightTons) {
+        const [sum]: Array<{ tons: string | null }> = await manager.query(
+          `SELECT SUM(bcu.vgm_tons) AS tons
+             FROM freight.booking_container_units bcu
+             JOIN freight.booking_container bc
+               ON bc.id = bcu.booking_container_id AND bc.deleted_at IS NULL
+            WHERE bc.booking_id = $1 AND bcu.deleted_at IS NULL`,
+          [booking.id],
+        );
+        weightTons = Number(sum?.tons) || null;
+      }
+
       const repo = manager.getRepository(FacilityHandlingEvent);
       await repo.save(
         repo.create({
@@ -75,7 +90,7 @@ export class FacilityHandlingService {
           trainScheduleId: input.trainScheduleId ?? null,
           eventType,
           grnNumber,
-          weightTons: Number(booking.cargoTotalWeightVgm) || null,
+          weightTons,
           inventoryId,
           performedBy: input.performedBy ?? null,
           occurredAt,