Soroban contract test coverage measurement + CI gate

[truthixify]

Tier: M (2-4 days) Type: test

Context

No coverage measurement today. For security-critical Stellar contracts we should know what % of branches the test suite touches and prevent regressions.

Scope

• Set up cargo-tarpaulin (or cargo-llvm-cov) for the Soroban workspace
• Target 90%+ coverage for stealth-announcer, stealth-registry, stealth-sender
• Target 80%+ for wraith-names and stealth-splitter
• CI gate fails when coverage drops below threshold
• HTML report uploaded as artifact

Acceptance criteria

• Coverage tooling integrated
• Per-contract threshold enforcement in CI
• First-run report committed as baseline
• Documentation in stellar/README.md

Files to start with

• stellar/Cargo.toml (workspace config)
• .github/workflows/

[Mubking-dev]

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

Hi, I'm Mubaraq — a Full-Stack & Blockchain Developer with 3+ years of experience. I've reviewed this issue and I'm confident I can handle it. I'll submit a clean PR within 2–3 days. Please assign it to me!

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

[drips-wave]

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

🧑‍💻 @Mubking-dev: 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 🌊

[truthixify]

@Mubking-dev Assigned. Welcome to wave 6.

Quick expectations to make this smooth for both sides:

1. Branch from develop (not main). PRs target develop.
2. Open a draft PR within ~3 days of pickup so we can see direction early.
3. Update at least every 5 days. If you get stuck or context changes, just say so on the PR — silence is the only thing that costs you the assignment.
4. Read the issue body's acceptance criteria carefully. Hitting those is the merge bar.

If anything is ambiguous, ask before building. Looking forward to the PR.