Implement autobackup-operator controllers, tests, CI and packaging

PVCs and CloudNativePG Clusters need S3 buckets and backup schedules
provisioned consistently. This operator watches the
backups.unkin.net/{schedule,destination} annotations on those objects and
provisions everything needed to back them up, with no new CRDs.

- Add a PVC controller that provisions cephrgw ObjectStoreUser/Bucket/BucketAccess,
  auto-generates a restic repo-password Secret and creates a k8up Schedule scoped
  to the PVC via spec.backup.volumes[].persistentVolumeClaim.claimName.
- Add a CNPG Cluster controller that provisions the same bucket stack, idempotently
  patches spec.backup.barmanObjectStore (leaving a user-set destinationPath alone
  with a Warning event) and creates a ScheduledBackup.
- Resolve destinations through a ConfigMap lookup table; requeue until the
  BucketAccess is Ready before creating schedule resources; own-reference created
  resources and retain bucket data by default.
- Add schedule-mapping helpers (k8up 5-field/shortcut pass-through, CNPG 6-field
  seconds-first) and deterministic, length-bounded name derivation.
- Add unit tests (schedule mapping, name derivation, destination resolution) and
  envtest controller tests for both paths, wiring the external CRDs into envtest.
- Add kubebuilder-generated RBAC, a Dockerfile (distroless/nonroot), Woodpecker
  lint/test/build pipelines and a tag-triggered image push to the artifactapi
  docker-internal registry, plus a version-bump Makefile and deploy manifests.

vendor/sigs.k8s.io/controller-runtime/pkg/handler/enqueue.go

@@ -0,0 +1,120 @@
+/*
+Copyright 2018 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package handler
+
+import (
+	"context"
+	"reflect"
+
+	"k8s.io/apimachinery/pkg/types"
+	"k8s.io/client-go/util/workqueue"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+	"sigs.k8s.io/controller-runtime/pkg/event"
+	logf "sigs.k8s.io/controller-runtime/pkg/internal/log"
+	"sigs.k8s.io/controller-runtime/pkg/reconcile"
+)
+
+var enqueueLog = logf.RuntimeLog.WithName("eventhandler").WithName("EnqueueRequestForObject")
+
+type empty struct{}
+
+var _ EventHandler = &EnqueueRequestForObject{}
+
+// EnqueueRequestForObject enqueues a Request containing the Name and Namespace of the object that is the source of the Event.
+// (e.g. the created / deleted / updated objects Name and Namespace). handler.EnqueueRequestForObject is used by almost all
+// Controllers that have associated Resources (e.g. CRDs) to reconcile the associated Resource.
+type EnqueueRequestForObject = TypedEnqueueRequestForObject[client.Object]
+
+// TypedEnqueueRequestForObject enqueues a Request containing the Name and Namespace of the object that is the source of the Event.
+// (e.g. the created / deleted / updated objects Name and Namespace).  handler.TypedEnqueueRequestForObject is used by almost all
+// Controllers that have associated Resources (e.g. CRDs) to reconcile the associated Resource.
+//
+// TypedEnqueueRequestForObject is experimental and subject to future change.
+type TypedEnqueueRequestForObject[object client.Object] struct{}
+
+// Create implements EventHandler.
+func (e *TypedEnqueueRequestForObject[T]) Create(ctx context.Context, evt event.TypedCreateEvent[T], q workqueue.TypedRateLimitingInterface[reconcile.Request]) {
+	if isNil(evt.Object) {
+		enqueueLog.Error(nil, "CreateEvent received with no metadata", "event", evt)
+		return
+	}
+
+	item := reconcile.Request{NamespacedName: types.NamespacedName{
+		Name:      evt.Object.GetName(),
+		Namespace: evt.Object.GetNamespace(),
+	}}
+
+	addToQueueCreate(q, evt, item)
+}
+
+// Update implements EventHandler.
+func (e *TypedEnqueueRequestForObject[T]) Update(ctx context.Context, evt event.TypedUpdateEvent[T], q workqueue.TypedRateLimitingInterface[reconcile.Request]) {
+	switch {
+	case !isNil(evt.ObjectNew):
+		item := reconcile.Request{NamespacedName: types.NamespacedName{
+			Name:      evt.ObjectNew.GetName(),
+			Namespace: evt.ObjectNew.GetNamespace(),
+		}}
+
+		addToQueueUpdate(q, evt, item)
+	case !isNil(evt.ObjectOld):
+		item := reconcile.Request{NamespacedName: types.NamespacedName{
+			Name:      evt.ObjectOld.GetName(),
+			Namespace: evt.ObjectOld.GetNamespace(),
+		}}
+
+		addToQueueUpdate(q, evt, item)
+	default:
+		enqueueLog.Error(nil, "UpdateEvent received with no metadata", "event", evt)
+	}
+}
+
+// Delete implements EventHandler.
+func (e *TypedEnqueueRequestForObject[T]) Delete(ctx context.Context, evt event.TypedDeleteEvent[T], q workqueue.TypedRateLimitingInterface[reconcile.Request]) {
+	if isNil(evt.Object) {
+		enqueueLog.Error(nil, "DeleteEvent received with no metadata", "event", evt)
+		return
+	}
+	q.Add(reconcile.Request{NamespacedName: types.NamespacedName{
+		Name:      evt.Object.GetName(),
+		Namespace: evt.Object.GetNamespace(),
+	}})
+}
+
+// Generic implements EventHandler.
+func (e *TypedEnqueueRequestForObject[T]) Generic(ctx context.Context, evt event.TypedGenericEvent[T], q workqueue.TypedRateLimitingInterface[reconcile.Request]) {
+	if isNil(evt.Object) {
+		enqueueLog.Error(nil, "GenericEvent received with no metadata", "event", evt)
+		return
+	}
+	q.Add(reconcile.Request{NamespacedName: types.NamespacedName{
+		Name:      evt.Object.GetName(),
+		Namespace: evt.Object.GetNamespace(),
+	}})
+}
+
+func isNil(arg any) bool {
+	if v := reflect.ValueOf(arg); !v.IsValid() || ((v.Kind() == reflect.Ptr ||
+		v.Kind() == reflect.Interface ||
+		v.Kind() == reflect.Slice ||
+		v.Kind() == reflect.Map ||
+		v.Kind() == reflect.Chan ||
+		v.Kind() == reflect.Func) && v.IsNil()) {
+		return true
+	}
+	return false
+}