[easy] Add an example script that lists the CAIP-2 network identifiers used

[davedumto]

Summary

Add a standalone example script under contrib/examples/ that prints the CAIP-2 network identifiers the SDK works with, such as stellar:testnet and stellar:pubnet.

Requirements

• File lives under contrib/examples/list-caip2-ids/ with a short README.
• Includes both the testnet and mainnet identifiers with a short label each.
• No network calls, purely a constant lookup and print.
• Include a short note in the README on where these identifiers are used in the SDK.

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.

[AbdulHameedAnofi]

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

I will like to resolve this issues

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

[drips-wave]

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

🧑‍💻 @AbdulHameedAnofi: 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

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🌊 Happy Wave 🌊

[drips-wave]

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

😎 @AbdulHameedAnofi: 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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