feat(warehouse,last-mile): truck load size rule, dedup last-mile, driver-required + arrival prefill

Truck loading:
- loadTruck enforces max 2 containers / one 40ft (two 20ft) and auto-marks an
  assigned truck arrived on load; container-items payload + modal expose
  container size with a client-side selection cap.
- Show "#x containers pending assignment" in the portal truck card and the
  backoffice container modal.

Last-mile:
- create() is idempotent — return the existing record for a booking instead of
  inserting a duplicate delivery row (fixed the same booking showing twice in
  Assign-Mile).
- setVehicles/update reject a truck with no assigned driver; the Assign toast
  now surfaces the reason.
- New GET /last-mile/booking/:id/arrival-trucks returns assigned EDR trucks with
  driver details; ReleaseOrderModal fetches and auto-fills them so an assigned
  EDR truck no longer reads as "not assigned yet".

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

apps/edr-freight-api/src/modules/last-mile/last-mile.controller.ts

@@ -67,6 +67,12 @@ export class LastMileController {
     return this.lastMileService.findById(id);
   }
 
+  @Get('booking/:bookingId/arrival-trucks')
+  @ApiOperation({ summary: "Assigned EDR last-mile trucks for a booking (arrival/exit weighing prefill)" })
+  arrivalTrucks(@Param('bookingId', ParseUUIDPipe) bookingId: string) {
+    return this.lastMileService.arrivalTrucksForBooking(bookingId);
+  }
+
   @Post('accept/:reference')
   @BookingStaff(FREIGHT_PERMS.lastMile.accept)
   @ApiOperation({ summary: 'Accept a paid booking and create a last-mile leg' })