Add Pod Security Standards reference to security guidance

[reyhankoyun]

Description

Why is this change being made?

1. Add reference to Kubernetes Pod Security Standards documentation so operators are aware of cluster-level hardening options.

What is changing?

1. Added a one-line link to the Kubernetes PSS documentation in the existing Security Considerations section of the README.

Related Links

• Issue #, if available: N/A

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Testing

How was this tested?

1. Documentation-only change — no code or behavior changes.

When testing locally, provide testing artifact(s):

1. N/A — README change only.

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Reviewee Checklist

Update the checklist after submitting the PR

• I have reviewed, tested and understand all changes
  If not, why:
• I have filled out the Description and Testing sections above
  If not, why:
• Build and Unit tests are passing
  If not, why: No code changes
• Unit test coverage check is passing
  If not, why: No code changes
• Integration tests pass locally
  If not, why: No code changes
• I have updated integration tests (if needed)
  If not, why: Not needed — documentation only
• I have ensured no sensitive information is leaking (i.e., no logging of sensitive fields, or otherwise)
  If not, why:
• I have added explanatory comments for complex logic, new classes/methods and new tests
  If not, why: N/A
• I have updated README/documentation (if needed)
  If not, why: This is the README update
• I have clearly called out breaking changes (if any)
  If not, why: No breaking changes

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Reviewer Checklist

All reviewers please ensure the following are true before reviewing:

• Reviewee checklist has been accurately filled out
• Code changes align with stated purpose in description
• Test coverage adequately validates the changes

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 60.97%. Comparing base (13af9ae) to head (d615146).

Additional details and impacted files

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  Coverage   60.97%   60.97%           
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  Files          11       11           
  Lines         720      720           
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  Hits          439      439           
  Misses        263      263           
  Partials       18       18           

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[secrets-manager-ai-code-review]

Claude finished @reyhankoyun's task in 26s —— View job

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Code Review

• Read the PR diff and surrounding README context
• Assessed the change for quality, correctness, and placement

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This is a clean, documentation-only change that adds a reference to the Kubernetes Pod Security Standards in the Security Considerations section of the README.

Assessment:

• ✅ Placement — The new line sits logically under ### Security Considerations (README.md:366), right after the existing note on secret handling. Good contextual fit for cluster-hardening guidance.
• ✅ Markdown — Link syntax is correct and the surrounding blank lines are consistent with the rest of the file.
• ✅ Link target — Points to the canonical Kubernetes PSS docs (a stable, versionless URL under kubernetes.io/docs/concepts/), which is the right choice for long-term durability.
• ✅ No code/security/performance impact — Documentation only; the codecov report confirms 0 line changes to coverable code.

Minor (optional, non-blocking) suggestions:

• The link text and target are both generic "cluster hardening." Since this is a CSI provider that mounts secrets to the filesystem, you could optionally tie the guidance more directly to this project — e.g. a brief note that operators may want to run provider/consumer pods under the restricted PSS profile, or a pointer to running with a read-only root filesystem and dropped capabilities. Purely additive; the current one-liner is already a net improvement.

Nothing here blocks merge. LGTM. 👍