[Wave 7 4/10] Explorer URL builder tests for Sepolia and Stellar testnet

[karagozemin]

Summary

OverSync docs and UI rely on explorer links for reviewer verification. Add a centralized explorer URL builder and tests for Sepolia, Ethereum mainnet-disabled paths, Stellar testnet, and Stellar public network placeholders.

High reviewer value, easy utility/tests.

Scope

• Add or centralize explorer URL helpers for transaction, address, and Soroban contract IDs.
• Cover Sepolia Etherscan and StellarExpert testnet URLs.
• Ensure unknown network values fail clearly or return null instead of malformed links.
• Add tests for tx hash, EVM address, Stellar account, and Soroban contract id.

Guardrails

• Do not enable mainnet UI paths.
• Do not hard-code fake transaction hashes.
• Keep helper pure and dependency-free.

Acceptance criteria

• Explorer links are generated consistently.
• Invalid network/input cases are tested.
• Existing frontend/history tests pass.

Wave complexity (maintainer)

High - 200 points

[Killerjunior]

@Killerjunior has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi maintainer, I have read and understood the issue requirements and checked the necessary documentation. I’m confident I can work on this task effectively and deliver a proper solution.

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

[Peaostrel]

@Peaostrel has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

i can handle this quickly

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[Olasunkanmi975]

@Olasunkanmi975 has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Please assign

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[Oluwasuyi-Oluwatimilehin-Daniel]

@Oluwasuyi-Timilehin has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hello maintainer, please assign me to this task. I would get started immediately

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

[AdeMi20]

@AdeMi20 has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi i will like to take these issue pls

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[Olajcodes]

@Olajcodes has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi maintainer, kindly assign this issue to me. I have worked on issue like this before. I believe I'm capable.

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

[drips-wave]

Congratulations, @laxjovial! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 30, 2026.

🧑‍💻 @laxjovial: 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 🌊