add hard capacity ceiling to weight limit rules

apps/edr-freight-api/src/modules/contracts/contract-booking.service.ts

@@ -133,6 +133,13 @@ export class ContractBookingService {
       });
     }
 
+    // Hard capacity gate: a container line whose total weight exceeds the
+    // container type's max capacity can never be booked — no surcharge path,
+    // no override. Checked before any row is written.
+    if (freightType === 'CONTAINER') {
+      await this.assertWithinMaxCapacity(contract, dto);
+    }
+
     // Denormalize route/direction/freight onto the booking for the scheduling engine.
     const booking = await this.bookingsRepository.create({
       reference,
@@ -608,6 +615,7 @@ export class ContractBookingService {
     overweightSurchargeAmount: number;
     currency: string | null;
     pairingErrors: string[];
+    capacityErrors: string[];
     lineItems: PriceLineItemDto[];
     totalAmount: number;
   }> {
@@ -621,6 +629,7 @@ export class ContractBookingService {
         overweightSurchargeAmount: 0,
         currency: null,
         pairingErrors: [],
+        capacityErrors: [],
         lineItems: [],
         totalAmount: 0,
       };
@@ -695,16 +704,63 @@ export class ContractBookingService {
       (v) => v.message,
     );
 
+    // Hard capacity ceiling — a non-empty result means the create call will be
+    // rejected, so the form can block submit up front.
+    const capacityErrors = await this.ruleEngineService.capacityViolations(
+      resolved.map(({ line, ct, totalVgmTons }) => ({
+        containerTypeId: ct.id,
+        quantity: line.quantity,
+        totalVgmTons,
+      })),
+      contract.tradeDirection,
+    );
+
     return {
       overweightLines: computed.overweightLines,
       overweightSurchargeAmount,
       currency: computed.currency,
       pairingErrors,
+      capacityErrors,
       lineItems: computed.lineItems,
       totalAmount: computed.totalAmount,
     };
   }
 
+  /**
+   * Throws when any container line's total weight exceeds the hard capacity
+   * ceiling of its weight limit rule. Mirrors validateShipment's line
+   * resolution so the gate matches what the form preview reported.
+   */
+  private async assertWithinMaxCapacity(
+    contract: Contract,
+    dto: CreateBookingUnderContractDto,
+  ): Promise<void> {
+    const lines = dto.containers ?? [];
+    if (!lines.length) return;
+
+    const containers = await Promise.all(
+      lines.map(async (line) => {
+        const ct = await this.resolveContainerTypeForSize(
+          line.containerSize,
+          contract.isReefer || (line.reeferQuantity ?? 0) > 0,
+        );
+        const totalVgmTons = (line.units ?? []).reduce(
+          (s, u) => s + Number(u.vgmTons ?? 0),
+          0,
+        );
+        return { containerTypeId: ct.id, quantity: line.quantity, totalVgmTons };
+      }),
+    );
+
+    const violations = await this.ruleEngineService.capacityViolations(
+      containers,
+      contract.tradeDirection,
+    );
+    if (violations.length) {
+      throw new BadRequestException(violations.join('; '));
+    }
+  }
+
   private async max20ftPairDiffTons(): Promise<number> {
     const row = await this.dataSource
       .getRepository(TrainSchedulingGlobalRules)