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/contracts/contract-booking.service.ts

@@ -140,6 +140,14 @@ export class ContractBookingService {
     dto: CreateBookingUnderContractDto,
     user?: { id?: string } | null,
     actorPermissions?: unknown,
+    opts?: {
+      /**
+       * Wagon-cancellation credit rebook only: the freight was paid while the
+       * contract was live, so redeeming the credit is allowed even after the
+       * contract's validity lapsed. Never set for a genuinely new booking.
+       */
+      allowExpiredContract?: boolean;
+    },
   ): Promise<CreateBookingUnderContractResult> {
     const contract = await this.contractsRepository.findByIdWithRelations(contractId);
     if (!contract) throw new NotFoundException(`Contract ${contractId} not found`);
@@ -180,8 +188,13 @@ export class ContractBookingService {
       actorPermissions != null &&
       hasFreightPermission(actorPermissions, FREIGHT_PERMS.contracts.createBooking);
 
-    await this.assertNotExpired(contract);
-    const createdByRole = await this.assertGate(contract, isGlActor);
+    if (!opts?.allowExpiredContract) await this.assertNotExpired(contract);
+    const createdByRole = await this.assertGate(
+      contract,
+      isGlActor,
+      false,
+      opts?.allowExpiredContract,
+    );
 
     // ONE_TIME: a single shipment at a time. The slot frees only if the prior
     // booking reached a terminal state (e.g. payment expired without shipping),
@@ -1203,6 +1216,7 @@ export class ContractBookingService {
     contract: Contract,
     isGlActor: boolean,
     isInitiate = false,
+    allowExpired = false,
   ): Promise<string> {
     // Suspended contracts are frozen for everyone, GL included — say so instead
     // of letting the executed-status check below give a misleading reason.
@@ -1225,7 +1239,10 @@ export class ContractBookingService {
       }
       // No contract clearance cycle exists on either kind now — clearance runs
       // on the booking, so an executed/active contract is the only gate here.
-      if (!['FULLY_EXECUTED', 'CONTRACT_ACTIVE'].includes(contract.status)) {
+      if (
+        !['FULLY_EXECUTED', 'CONTRACT_ACTIVE'].includes(contract.status) &&
+        !(allowExpired && contract.status === 'EXPIRED')
+      ) {
         throw new BadRequestException(
           'Contract must be fully executed before booking a shipment.',
         );
@@ -1234,7 +1251,10 @@ export class ContractBookingService {
     }
 
     // Path A — customer (or staff) once the contract is executed.
-    if (!['FULLY_EXECUTED', 'CONTRACT_ACTIVE'].includes(contract.status)) {
+    if (
+      !['FULLY_EXECUTED', 'CONTRACT_ACTIVE'].includes(contract.status) &&
+      !(allowExpired && contract.status === 'EXPIRED')
+    ) {
       throw new BadRequestException(
         'Contract must be fully executed before booking a shipment.',
       );

apps/edr-freight-api/src/modules/contracts/contract-expired-rebook-gate.spec.ts

@@ -0,0 +1,65 @@
+import { ContractBookingService } from './contract-booking.service';
+
+/**
+ * Wagon-cancellation credit rebook must work after the contract lapses (the
+ * freight was paid while it was live), while every other create path stays
+ * blocked. assertGate is the status gate createUnderContract runs; this pins
+ * the EXPIRED carve-out to the allowExpired flag.
+ */
+describe('ContractBookingService.assertGate expired-contract rebook carve-out', () => {
+  // assertGate only reads contract fields — no constructor deps needed.
+  const service = Object.create(
+    ContractBookingService.prototype,
+  ) as ContractBookingService;
+  const gate = (
+    contract: Record<string, unknown>,
+    allowExpired: boolean,
+  ): Promise<string> =>
+    (
+      service as unknown as {
+        assertGate: (
+          c: unknown,
+          gl: boolean,
+          init: boolean,
+          allowExpired: boolean,
+        ) => Promise<string>;
+      }
+    ).assertGate(contract, true, false, allowExpired);
+
+  it('refuses an EXPIRED contract on the normal create path', async () => {
+    await expect(
+      gate({ status: 'EXPIRED', contractKind: 'GENERAL' }, false),
+    ).rejects.toThrow(/fully executed/i);
+  });
+
+  it('lets a credit rebook through on an EXPIRED contract (Path A)', async () => {
+    await expect(
+      gate({ status: 'EXPIRED', contractKind: 'GENERAL' }, true),
+    ).resolves.toBe('STAFF');
+  });
+
+  it('lets a credit rebook through on an EXPIRED customs contract (Path B)', async () => {
+    await expect(
+      gate(
+        {
+          status: 'EXPIRED',
+          contractKind: 'GENERAL',
+          customsClearingEnabled: true,
+        },
+        true,
+      ),
+    ).resolves.toBe('GL_ET');
+  });
+
+  it('still refuses a SUSPENDED contract even for a rebook', async () => {
+    await expect(
+      gate({ status: 'SUSPENDED', contractKind: 'GENERAL' }, true),
+    ).rejects.toThrow(/suspended/i);
+  });
+
+  it('does not open the gate for other non-executed statuses', async () => {
+    await expect(
+      gate({ status: 'DRAFT', contractKind: 'GENERAL' }, true),
+    ).rejects.toThrow(/fully executed/i);
+  });
+});