fix(lint): resolve all golangci-lint findings

Migrate the lint config to the v2 format.
Replace the deprecated scheme.Builder with runtime.NewSchemeBuilder.
Handle Close errors in the worker and replace repeated strings with constants.
Remove unused parameters and use switch statements where the linter asks.

api/raczylo.com/v1/clusterimage_types.go

@@ -19,6 +19,7 @@ package v1
 import (
 	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
 )
 
 // ClusterImageSpec defines the desired state of ClusterImage
@@ -81,5 +82,8 @@ type ClusterImageList struct {
 }
 
 func init() {
-	SchemeBuilder.Register(&ClusterImage{}, &ClusterImageList{})
+	SchemeBuilder.Register(func(s *runtime.Scheme) error {
+		s.AddKnownTypes(GroupVersion, &ClusterImage{}, &ClusterImageList{})
+		return nil
+	})
 }

api/raczylo.com/v1/clusterimageexport_types.go

@@ -19,6 +19,7 @@ package v1
 import (
 	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
 )
 
 // RetentionPolicy defines how many completed ClusterImageExport resources to keep
@@ -136,5 +137,8 @@ type ClusterImageExportList struct {
 }
 
 func init() {
-	SchemeBuilder.Register(&ClusterImageExport{}, &ClusterImageExportList{})
+	SchemeBuilder.Register(func(s *runtime.Scheme) error {
+		s.AddKnownTypes(GroupVersion, &ClusterImageExport{}, &ClusterImageExportList{})
+		return nil
+	})
 }

api/raczylo.com/v1/groupversion_info.go

@@ -20,8 +20,9 @@ limitations under the License.
 package v1
 
 import (
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/schema"
-	"sigs.k8s.io/controller-runtime/pkg/scheme"
 )
 
 var (
@@ -29,7 +30,10 @@ var (
 	GroupVersion = schema.GroupVersion{Group: "raczylo.com", Version: "v1"}
 
 	// SchemeBuilder is used to add go types to the GroupVersionKind scheme
-	SchemeBuilder = &scheme.Builder{GroupVersion: GroupVersion}
+	SchemeBuilder = runtime.NewSchemeBuilder(func(s *runtime.Scheme) error {
+		metav1.AddToGroupVersion(s, GroupVersion)
+		return nil
+	})
 
 	// AddToScheme adds the types in this group-version to the given scheme.
 	AddToScheme = SchemeBuilder.AddToScheme