rbd: use StorageClass image features for temp clones and snapshots (backport #6205)

[mergify]

Describe what this PR does

Previously, temporary clone images (-temp) and snapshot backing images
had their features hard-coded to only layering and deep-flatten.

Inherit the image features from the parent volume (configured via
StorageClass imageFeatures) while ensuring layering and deep-flatten
are always enabled, as they are required for the flatten operation.

Fixes: #4936

Checklist:

• Commit Message Formatting: Commit titles and messages follow. guidelines in the developer guide.
• Reviewed the developer guide on Submitting a Pull Request
• Pending release notes updated with breaking and/or notable changes for the next major release.
• Documentation has been updated, if necessary.
• Unit tests have been added, if necessary.
• Integration tests have been added, if necessary.

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---

This is an automatic backport of pull request #6205 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of 0e81334 has failed:

On branch mergify/bp/release-v3.16/pr-6205
Your branch is ahead of 'origin/release-v3.16' by 1 commit.
  (use "git push" to publish your local commits)

You are currently cherry-picking commit 0e81334a.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   e2e/rbd.go
	both modified:   e2e/rbd_helper.go

no changes added to commit (use "git add" and/or "git commit -a")

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

[iPraveenParihar]

conflicts in e2e because of By() changed to It(). @Rakshith-R , do you think we might need to backport #6136?
Or I'll just convert the It() to By() in previous release?

[nixpanic]

conflicts in e2e because of By() changed to It(). @Rakshith-R , do you think we might need to backport #6136? Or I'll just convert the It() to By() in previous release?

Please just use By() instead, don't backport the complete e2e change (it also may have additional tests not suitable for release-3.16).

[ceph-csi-bot]

/test ci/centos/k8s-e2e-external-storage/1.33

[ceph-csi-bot]

/test ci/centos/k8s-e2e-external-storage/1.32

[ceph-csi-bot]

/test ci/centos/upgrade-tests-cephfs

[ceph-csi-bot]

/test ci/centos/mini-e2e-helm/k8s-1.33

[ceph-csi-bot]

/test ci/centos/mini-e2e-helm/k8s-1.32

[ceph-csi-bot]

/test ci/centos/upgrade-tests-rbd

[ceph-csi-bot]

/test ci/centos/mini-e2e/k8s-1.33

[ceph-csi-bot]

/test ci/centos/k8s-e2e-external-storage/1.34

[ceph-csi-bot]

/test ci/centos/mini-e2e/k8s-1.32

[ceph-csi-bot]

/test ci/centos/mini-e2e-helm/k8s-1.34

[ceph-csi-bot]

/test ci/centos/mini-e2e/k8s-1.34

[nixpanic]

@iPraveenParihar , feel free to approve this :)

[mergify]

Merge Queue Status

• ✅ Entered queue — 2026-04-03 09:29 UTC · Rule: default
• ✅ Checks started · in-place
• 🚫 Left the queue — 2026-04-03 15:35 UTC · at 27f9c96138411f1128aa00f58dd296129bed1360

This pull request spent 6 hours 6 minutes 30 seconds in the queue, with no time running CI.

Required conditions to merge

• #approved-reviews-by >= 1 [🛡 GitHub branch protection]
  • rbd: use StorageClass image features for temp clones and snapshots (backport #6205) #6217
• #changes-requested-reviews-by = 0 [🛡 GitHub branch protection]
  • rbd: use StorageClass image features for temp clones and snapshots (backport #6205) #6217

Reason

The merge conditions cannot be satisfied due to failing checks

Hint

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