Pause scheduled backups

[eminano]

This PR updates the scale to zero sidecar behaviour to suspend the cluster scheduled backups if any after the cluster is successfully hibernated to prevent errors.

https://cloudnative-pg.io/documentation/1.26/backup/#pause-scheduled-backups

[Copilot]

Pull Request Overview

This PR implements the ability to pause scheduled backups when a cluster is hibernated by the scale-to-zero sidecar, preventing backup errors on inactive clusters.

• Adds RBAC permissions for scheduledbackups resources
• Implements scheduled backup management functionality in the sidecar
• Updates documentation to reflect the new backup pause behavior

Reviewed Changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
manifest.yaml	Adds scheduledbackups to RBAC resources
manifest-dev.yaml	Adds scheduledbackups to RBAC resources
kubernetes/rbac.yaml	Updates RBAC to include scheduledbackups with required verbs
internal/sidecar/sidecar.go	Registers ScheduledBackup types in the runtime scheme
internal/sidecar/scale_to_zero_test.go	Adds comprehensive test coverage for scheduled backup scenarios
internal/sidecar/scale_to_zero.go	Implements core backup pause logic and cluster client interface
internal/sidecar/helper_test.go	Adds mock methods for scheduled backup operations
internal/sidecar/cluster_client.go	Implements scheduled backup client operations
doc/examples/cluster-example.yaml	Adds example ScheduledBackup resource
doc/development.md	Documents new scheduled backup management features
README.md	Updates documentation with backup management information

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[simonapencea]

Not sure where to add this comment, so adding it here:there is a corner case where we may still have issues:

if we try to hibernate a cluster while a full backup that the scheduledbackup triggered is going on.

I think the easiest would be to not hibernate until the backup completes. However, it would be complicated to expose this to the customer as of right now, since we are not exposing backups to them yet.
After we expose the backups to the customer, we could go for something like that - basically say - we cannot hibernate your cluster, because it is during the backup window and there is an active backup
Is that easy to add?

Alternatively, we could hibernate and let the backup fail, but that would potentially give us some unusable files in S3. We need to probably test a bit to see exactly what happens and what would be more straightforward for us.

But for now, this is a big improvement already.

[github-actions]

🧹 PR Resources Cleaned Up

Since this PR has been merged, the following test resources have been automatically deleted:

• Container images: pr-18-*
• Kubernetes manifest artifacts

Thanks for testing! 🎉