feat(customer): order history and detail for the customer app

Adds GET /customer/orders and GET /customer/orders/:id for the customer
app: the orders linked to the logged-in customer across their
organization's outlets, newest first, paginated (limit 1-100, default 20).

The list shows the order number, outlet, type, status, total, item count,
void/refund flags and the EnakPoint and EnakCoin it earned. The detail adds
the amounts, the items with product and variant names, weight and unit
for weighed lines, modifiers and notes, and the payments with the method
and, for EnakPoint, the points used. Costs, cashier and other internal
fields are left out. Another customer's order answers 404 like one that
does not exist.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/service/customer_order_service.go

@@ -0,0 +1,57 @@
+package service
+
+import (
+	"context"
+	"errors"
+
+	"github.com/google/uuid"
+
+	"apskel-pos-be/internal/constants"
+	"apskel-pos-be/internal/contract"
+	"apskel-pos-be/internal/models"
+	"apskel-pos-be/internal/processor"
+	"apskel-pos-be/internal/repository"
+)
+
+// CustomerOrderService serves the customer app's order history.
+type CustomerOrderService interface {
+	List(ctx context.Context, customerID uuid.UUID, query models.ListCustomerOrdersQuery) *contract.Response
+	Detail(ctx context.Context, customerID, orderID uuid.UUID) *contract.Response
+}
+
+type CustomerOrderServiceImpl struct {
+	orders *processor.CustomerOrderProcessor
+}
+
+func NewCustomerOrderService(orders *processor.CustomerOrderProcessor) *CustomerOrderServiceImpl {
+	return &CustomerOrderServiceImpl{orders: orders}
+}
+
+func (s *CustomerOrderServiceImpl) List(ctx context.Context, customerID uuid.UUID, query models.ListCustomerOrdersQuery) *contract.Response {
+	orders, err := s.orders.List(ctx, customerID, query)
+	if err != nil {
+		return customerOrderErrorResponse(err)
+	}
+	return contract.BuildSuccessResponse(orders)
+}
+
+func (s *CustomerOrderServiceImpl) Detail(ctx context.Context, customerID, orderID uuid.UUID) *contract.Response {
+	order, err := s.orders.Detail(ctx, customerID, orderID)
+	if err != nil {
+		return customerOrderErrorResponse(err)
+	}
+	return contract.BuildSuccessResponse(order)
+}
+
+func customerOrderErrorResponse(err error) *contract.Response {
+	code := constants.InternalServerErrorCode
+	switch {
+	case errors.Is(err, repository.ErrCustomerOrderNotFound):
+		code = constants.NotFoundErrorCode
+	case errors.Is(err, processor.ErrInvalidWalletQuery):
+		code = constants.ValidationErrorCode
+	}
+	return contract.BuildErrorResponse([]*contract.ResponseError{
+		contract.NewResponseError(code, constants.RequestEntity, err.Error()),
+	})
+}