refactor: make createAuthenticatedUser accept interface and add user-only variant

internal/integration/helpers.go

@@ -398,7 +398,11 @@ type authenticatedUser struct {
 	Token string
 }
 
-func createAuthenticatedUser(t *testing.T, authService *services.AuthFacade, userRepo repositories.UserRepository, username, email string) *authenticatedUser {
+type authServiceInterface interface {
+	Login(username, password string) (*services.AuthResult, error)
+}
+
+func createAuthenticatedUser(t *testing.T, authService authServiceInterface, userRepo repositories.UserRepository, username, email string) *authenticatedUser {
 	t.Helper()
 
 	password := "SecurePass123!"
@@ -429,6 +433,11 @@ func createAuthenticatedUser(t *testing.T, authService *services.AuthFacade, use
 	}
 }
 
+func createAuthenticatedUserOnly(t *testing.T, authService authServiceInterface, userRepo repositories.UserRepository, username, email string) *database.User {
+	t.Helper()
+	return createAuthenticatedUser(t, authService, userRepo, username, email).User
+}
+
 func uniqueTestUsername(t *testing.T, prefix string) string {
 	return fmt.Sprintf("%s_%d_%d", prefix, time.Now().UnixNano(), len(t.Name()))
 }