Support adding annotation to pvc

[labuladong]

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[Copilot]

Pull Request Overview

This PR introduces optional metadata annotations and labels for the PVCs used in BookKeeper storage, enhancing configuration flexibility for journal and ledger volumes.

• Updated values.yaml files for both sn-platform and sn-platform-slim to include example metadata comments.
• Updated bookkeeper-cluster.yaml templates in both charts to conditionally render metadata for PVCs based on provided configuration.

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
charts/sn-platform/values.yaml	Added commented sample metadata configurations for journal and ledger.
charts/sn-platform/templates/bookkeeper/bookkeeper-cluster.yaml	Added conditional rendering for PVC metadata in journal and ledger sections.
charts/sn-platform-slim/values.yaml	Added commented sample metadata configurations for journal and ledger.
charts/sn-platform-slim/templates/bookkeeper/bookkeeper-cluster.yaml	Added conditional rendering for PVC metadata in journal and ledger sections.

[github-actions]

@labuladong:Thanks for your contribution. For this PR, do we need to update docs?
(The PR template contains info about doc, which helps others know more about the changes. Can you provide doc-related info in this and future PR descriptions? Thanks)