feat(train-scheduling): mid-route consist changes, audit history, safer workspace

- planned couples: loose wagons join the train at a route stop, added
  from the schedule yards tab; capacity credits them per corridor edge
  and coupling validates locomotive weight/length caps per leg
- real-cut toggle: a cut wagon permanently leaves the train build at
  its cut yard (soft cut still sits out one trip only)
- fix heaviest-leg display counting a shared slot's full cargo on
  every spanned edge (phantom pull-weight overload on S-2026-00045)
- confirmation dialogs for workspace add/load/unload/remove actions
- train-builder History and Detached-wagons tabs, backed by paginated
  endpoints; builder detaches now always write adjustment-log rows

Migrations 3660 (planned_wagon_couples, planned_wagon_real_cuts) and
3670 (adjustment log train_schedule_id nullable) — both applied to the
dev DB by hand; watch mode does not run migrations.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

apps/edr-freight-api/src/modules/train-scheduling/controllers/train-scheduling.controller.ts

@@ -222,7 +222,7 @@ export class TrainSchedulingController {
     @Param("id", ParseUUIDPipe) id: string,
     @Body() dto: UpdateScheduleWagonYardsDto,
   ) {
-    return this.trainSchedulingService.updateScheduleWagonYards(id, dto.moves);
+    return this.trainSchedulingService.updateScheduleWagonYards(id, dto);
   }
 
   @Post("schedules/:id/adjust-consist")