[easy] Add an example script that masks a secret key for safe logging

[davedumto]

Summary

Add a standalone example script under contrib/examples/ that masks all but the first few characters of a secret key string, suitable for safe logging.

Requirements

• File lives under contrib/examples/mask-secret/ with a short README.
• Exposes a small maskSecret function used by the script.
• Never logs or prints the full unmasked secret anywhere in the script.
• Include a few example inputs and expected masked outputs in the README.

Constraints

• Fork the repo, then create your branch from the drips branch (NOT main).
• Do ALL your work inside the contrib/ folder. Do not add, edit, rename,
  or delete any file outside contrib/.
• Open your PR against the drips branch. PRs targeting main are
  auto-closed. PRs targeting drips that touch files outside contrib/ are
  also auto-closed.
• Save your work under contrib/examples/ named after this issue (for example,
  contrib/examples/issue-42-name/).

Acceptance Criteria

• The change is entirely inside contrib/.
• The PR base branch is drips.
• Reviewed and approved by a maintainer before merge to drips.
• The maintainer will merge drips into main separately.

[KayProject]

@KayProject has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi Maintainer, I have carefully audited this issue and reviewed your preference so I would like to work on this issue

ℹ️ Repo Maintainers: To accept this application, review their application or assign @KayProject to this issue.

[dami080]

@dami080 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hello, I’ve gone over the requirements and am ready to deliver a solution that meets your acceptance criteria. Kindly assign this to me.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @dami080 to this issue.

[sublime247]

@sublime247 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

I will like to get on this

ℹ️ Repo Maintainers: To accept this application, review their application or assign @sublime247 to this issue.

[drips-wave]

Congratulations, @sublime247! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on August 31, 2026.

🧑‍💻 @sublime247: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

When opening a PR, please link it to this issue to ensure it gets tracked accurately. Points are awarded when this issue is marked as completed by the maintainer.

🤠 Repo maintainers: Please keep an eye on the contributor's progress and review their work before the due date. You can manage this issue, including adjusting its complexity and points, here.

🌊 Happy Wave 🌊

[drips-wave]

This issue has been completed by @sublime247 as part of the Stellar Wave Program's 8th Wave 🥳

😎 @sublime247: You earned 200 Points for completing this issue! After the current Wave ends, you'll be eligible for a percentage of the Wave's reward pool based on the percentage of total points you've earned. Learn more here. You can also Leave a review to share your experience working on this issue.

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