booking operations and trains scheduling also allocations

apps/edr-freight-api/src/modules/trains/entities/train.entity.ts

@@ -4,6 +4,10 @@ import { Freight } from '@edr/types';
 import { Column, Entity, OneToMany } from 'typeorm';
 import { Wagon } from '../../wagons/entities/wagon.entity';
 
+/**
+ * Fleet master data — named wagon consist in inventory (POST /trains).
+ * Operational departures use train_schedules + locomotives; scheduling never creates trains rows.
+ */
 @Entity({ schema: 'freight', name: 'trains' })
 export class Train extends BaseEntity {
   // --- existing fields (keep for backward compatibility) ---