feat(train): enhance train history and scheduling features

- Added a reason field to train history entries for detach/maintenance actions.
- Updated TrainHistoryPanel to display the reason for wagon detachments.
- Introduced per-wagon load/unload functionality in ScheduleWorkspacePanel with a modal for managing individual wagons.
- Implemented API endpoints for loading and unloading specific wagons, including the ability to cancel remaining wagons with a reason.
- Refactored detach request handling in TrainBuilderDetailPage to streamline the process and remove the approval flow, requiring a reason for detachments.
- Updated types and services to support new wagon loading/unloading features and booking wagon retrieval.

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

@@ -707,6 +707,46 @@ export class TrainSchedulingController {
     return this.bookingJourneyService.unloadBooking(id, bookingId);
   }
 
+  @Post("schedules/:id/bookings/:bookingId/wagons/:allocationId/load")
+  @TrainSchedulingLoad()
+  @ApiOperation({
+    summary:
+      "Confirm ONE wagon of the booking loaded (per-wagon loading). The booking stays PAID until every remaining wagon is LOADED; the last wagon runs the whole-booking load completion.",
+  })
+  loadScheduleBookingWagon(
+    @Param("id", ParseUUIDPipe) id: string,
+    @Param("bookingId", ParseUUIDPipe) bookingId: string,
+    @Param("allocationId", ParseUUIDPipe) allocationId: string,
+    @CurrentUser() user: AuthUserPayload,
+  ) {
+    return this.bookingJourneyService.loadWagon(
+      id,
+      bookingId,
+      allocationId,
+      resolveAuthUserId(user),
+    );
+  }
+
+  @Post("schedules/:id/bookings/:bookingId/wagons/:allocationId/unload")
+  @TrainSchedulingUnload()
+  @ApiOperation({
+    summary:
+      "Confirm ONE wagon of the booking unloaded (per-wagon unloading). The booking stays IN_TRANSIT until the last wagon, which runs the whole-booking unload completion.",
+  })
+  unloadScheduleBookingWagon(
+    @Param("id", ParseUUIDPipe) id: string,
+    @Param("bookingId", ParseUUIDPipe) bookingId: string,
+    @Param("allocationId", ParseUUIDPipe) allocationId: string,
+    @CurrentUser() user: AuthUserPayload,
+  ) {
+    return this.bookingJourneyService.unloadWagon(
+      id,
+      bookingId,
+      allocationId,
+      resolveAuthUserId(user),
+    );
+  }
+
   @Post("schedules/:id/intercity/:bookingId/load")
   @TrainSchedulingLoad()
   @ApiOperation({