fix(warehouses): truck-arrival crash on duplicate containers; auto-GRN on import unload

Truck Arrival died with "[@mantine/core] Duplicate options are not supported"
when a booking carried the same container number on two container lines (the
unit uniqueness is per line, not per booking):
- bookingContainerWeights now GROUPs BY container number (MAX weight)
- the weighing modal dedupes both the containers MultiSelect and the
  assigned-trucks Select defensively, so bad data degrades instead of
  crashing the whole page

Import GRN is now issued automatically when the arrived train is unloaded:
autoUnloadArrivedBookings stamps GRN-IMPORT-<date>-<booking> on both the
create and update paths (never overwrites an existing GRN). The per-row GRN
button in the import queue lights up with no extra clicks.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

apps/edr-freight-web/backoffice/src/components/warehouses/ReleaseOrderModal.tsx

@@ -202,8 +202,11 @@ export function ReleaseOrderModal({ opened, onClose, item, truckPrefill }: Relea
   ];
   // Only trucks actually assigned to THIS booking (last-mile prefill or customer
   // portal) are selectable. No global fleet list — if nothing is assigned, the
-  // operator types the plate manually in the field below.
-  const truckSelectOptions = assignedTruckOptions;
+  // operator types the plate manually in the field below. Deduped by plate:
+  // duplicate option values crash Mantine's Select.
+  const truckSelectOptions = [
+    ...new Map(assignedTruckOptions.map((t) => [t.value, t])).values(),
+  ];
   // Neither a last-mile truck nor a customer truck has been assigned yet.
   const noTruckAssigned = assignedTruckOptions.length === 0 && !isCustomerAssignedTruck;
   const isTruckIdentityLocked = isEntranceLocked || isCustomerAssignedTruck || hasLastMileTruckPrefill;
@@ -216,10 +219,19 @@ export function ReleaseOrderModal({ opened, onClose, item, truckPrefill }: Relea
   const containerWeightByNumber = new Map(
     containerWeights.map((c) => [c.containerNumber.toUpperCase(), Number(c.weightTons) || 0]),
   );
-  const containerSelectData = containerWeights.map((c) => ({
-    value: c.containerNumber,
-    label: `${c.containerNumber} · ${(Number(c.weightTons) || 0).toLocaleString()} t`,
-  }));
+  // Mantine Selects throw on duplicate option values — legacy bookings can carry
+  // the same container number on two lines, so dedupe defensively.
+  const containerSelectData = [
+    ...new Map(
+      containerWeights.map((c) => [
+        c.containerNumber,
+        {
+          value: c.containerNumber,
+          label: `${c.containerNumber} · ${(Number(c.weightTons) || 0).toLocaleString()} t`,
+        },
+      ]),
+    ).values(),
+  ];
   const selectedContainerNumbers = containerNumbers.map((n) => n.trim()).filter(Boolean);
   const selectedCargoWeight = Number(
     selectedContainerNumbers