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/github.com/go-openapi/jsonpointer/NOTICE

@@ -0,0 +1,39 @@
+Copyright 2015-2025 go-swagger maintainers
+
+// SPDX-FileCopyrightText: Copyright 2015-2025 go-swagger maintainers
+// SPDX-License-Identifier: Apache-2.0
+
+This software library, github.com/go-openapi/jsonpointer, includes software developed
+by the go-swagger and go-openapi maintainers ("go-swagger maintainers").
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this software except in compliance with the License.
+
+You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0.
+
+This software is copied from, derived from, and inspired by other original software products.
+It ships with copies of other software which license terms are recalled below.
+
+The original software was authored on 25-02-2013 by sigu-399 (https://github.com/sigu-399, sigu.399@gmail.com).
+
+github.com/sigh-399/jsonpointer
+===========================
+
+// SPDX-FileCopyrightText: Copyright 2013 sigu-399 ( https://github.com/sigu-399 )
+// SPDX-License-Identifier: Apache-2.0
+
+Copyright 2013 sigu-399 ( https://github.com/sigu-399 )
+
+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.