add per-container handling options for hazardous, reefer, and return services

- Introduced new boolean fields (isHazardous, isReefer, isReturn) in UnitDraft and related interfaces to allow individual container handling options.
- Updated emptyUnit function to initialize these new fields.
- Modified GlCreateBookingForm to handle and display these options for each container.
- Adjusted calculations for hazardous, reefer, and return quantities based on the new handling options.
- Updated the schema for container units and booking container lines to include handling options.
- Added migration to support the new return flag in the database.
- Enhanced various components to reflect gross weight calculations, ensuring consistency across the application.

apps/edr-freight-web/backoffice/src/components/trainScheduling/ScheduleWorkspacePanel.tsx

@@ -99,9 +99,8 @@ function usedWeight(schedule: TrainScheduleDetail): number {
 /**
  * Pull capacity of the set = the WEAKEST locomotive's max pull weight (0 when
  * unknown). The API caps at the weakest loco, not the sum of all locos — a
- * consist can only pull as hard as its weakest engine. Note: the API also adds
- * the consist tare to the used weight when it checks this cap; tare isn't
- * available client-side, so this meter compares cargo-only load against pull.
+ * consist can only pull as hard as its weakest engine. Both sides of this meter
+ * are gross: `usedWeight` sums per-booking gross (cargo + wagon tare).
  */
 function pullCapacity(schedule: TrainScheduleDetail): number {
   const set = schedule.trainSet;