Feat[BE]: integrate document service into expense module and update related DTOs for document handling

internal/modules/purchases/module.go

@@ -1,6 +1,7 @@
 package purchases
 
 import (
+	"context"
 	"fmt"
 
 	"github.com/go-playground/validator/v10"
@@ -41,6 +42,11 @@ func (PurchaseModule) RegisterRoutes(router fiber.Router, db *gorm.DB, validate
 
 	approvalRepo := commonRepo.NewApprovalRepository(db)
 	approvalService := commonSvc.NewApprovalService(approvalRepo)
+	documentRepo := commonRepo.NewDocumentRepository(db)
+	documentSvc, err := commonSvc.NewDocumentServiceFromConfig(context.Background(), documentRepo)
+	if err != nil {
+		panic(fmt.Sprintf("failed to create document service: %v", err))
+	}
 	if err := approvalService.RegisterWorkflowSteps(utils.ApprovalWorkflowPurchase, utils.PurchaseApprovalSteps); err != nil {
 		panic(fmt.Sprintf("failed to register purchase approval workflow: %v", err))
 	}
@@ -54,6 +60,7 @@ func (PurchaseModule) RegisterRoutes(router fiber.Router, db *gorm.DB, validate
 		approvalService,
 		expenseRealizationRepo,
 		projectFlockKandangRepository,
+		documentSvc,
 		validate,
 	)
 	expenseBridge := service.NewExpenseBridge(