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/swag/conv/format.go

@@ -0,0 +1,28 @@
+// SPDX-FileCopyrightText: Copyright 2015-2025 go-swagger maintainers
+// SPDX-License-Identifier: Apache-2.0
+
+package conv
+
+import (
+	"strconv"
+)
+
+// FormatInteger turns an integer type into a string.
+func FormatInteger[T Signed](value T) string {
+	return strconv.FormatInt(int64(value), 10)
+}
+
+// FormatUinteger turns an unsigned integer type into a string.
+func FormatUinteger[T Unsigned](value T) string {
+	return strconv.FormatUint(uint64(value), 10)
+}
+
+// FormatFloat turns a floating point numerical value into a string.
+func FormatFloat[T Float](value T) string {
+	return strconv.FormatFloat(float64(value), 'f', -1, bitsize(value))
+}
+
+// FormatBool turns a boolean into a string.
+func FormatBool(value bool) string {
+	return strconv.FormatBool(value)
+}