cmd: merge ship types

pkg/error/input.go

@@ -12,6 +12,10 @@ func NewEntityTypeNameDuplicateError(arg ...any) error {
 	return newGenericError(ErrInputEntityTypeNameDuplicate, arg...)
 }
 
+func NewEntityTypeNameEqualityError(arg ...any) error {
+	return newGenericError(ErrInputEntityTypeNameEquality, arg...)
+}
+
 func NewEntityNotExistsError(arg ...any) error {
 	return newGenericError(ErrInputEntityNotExists, arg...)
 }
@@ -59,3 +63,7 @@ func NewScienceSumValuesError(arg ...any) error {
 func NewProductionInvalidError(arg ...any) error {
 	return newGenericError(ErrInputProductionInvalid, arg...)
 }
+
+func NewMergeShipTypeNotEqualError(arg ...any) error {
+	return newGenericError(ErrMergeShipTypeNotEqual, arg...)
+}