feat: add contract extension request functionality

- Implemented  method in  to allow customers to request an extension for expired contracts.
- Added  component in  for users to initiate extension requests.
- Updated  to include logic for handling extension requests for expired contracts.
- Enhanced  to display extension request options and status.
- Created migration to add  and  columns to the contracts table.
- Added unit tests for contract extension request and handling in .
- Defined DTOs for request and extension in .
- Updated types in  to include new fields related to contract extensions.

apps/edr-freight-api/src/modules/train-scheduling/entities/train-scheduling-global-rules.entity.ts

@@ -3,6 +3,13 @@ import { Column, Entity } from 'typeorm';
 
 @Entity({ schema: 'freight', name: 'train_scheduling_global_rules' })
 export class TrainSchedulingGlobalRules extends BaseEntity {
+  /**
+   * LEGACY — `max_train_length_meters`, `max_train_weight_tons` and
+   * `max_20ft_container_weight_tons` are no longer read by planning: train
+   * weight/length come from locomotive configuration and per-box ceilings from
+   * the rule engine's weight limit rules (`max_capacity_tons`). Kept only so
+   * existing rows keep loading.
+   */
   @Column({
     name: 'max_train_length_meters',
     type: 'numeric',