Add code coverage reporting via Codecov

[ogazboiz]

Join our community: https://t.me/+DOylgFv1jyJlNzM0

Description

Tests run in CI but coverage is never measured or published. Without a baseline it is impossible to see if PRs are adding or eroding test coverage.

What Needs to Happen

• Add --coverage to backend Vitest config, output lcov report
• Upload backend lcov to Codecov in CI
• Run cargo tarpaulin on contracts and upload XML to Codecov
• Set minimum thresholds: 60% backend, 70% contracts — fail CI below threshold
• Add Codecov badge to README.md
• Enable Codecov PR comments showing diff coverage

Files

• .github/workflows/ci.yml
• backend/vitest.config.ts
• README.md

Acceptance Criteria

• Coverage badge on README
• CI fails if coverage drops below thresholds
• Codecov PR comments appear on every PR

[devkayazumi]

@devkayazumi has applied to work on this issue as part of the Stellar Wave Program's 4th wave.

Pls assign to me sir pls

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

[Vvictor-commits]

@Vvictor-commits has applied to work on this issue as part of the Stellar Wave Program's 4th wave.

please assign

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

[binayyub4211]

@binayyub4211 has applied to work on this issue as part of the Stellar Wave Program's 4th wave.

Hey maintainer

Can you please assign me I want to work on this issue

ℹ️ Repo Maintainers: To accept this application, review their application or assign @binayyub4211 to this issue.

[drips-wave]

Congratulations, @binayyub4211! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on April 29, 2026.

🧑‍💻 @binayyub4211: 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.

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🌊 Happy Wave 🌊