Implement Maximum Tags Per Invoice Enforcement

[Baskarayelu]

Description
Enforce a maximum number of tags per invoice (e.g. 10) in add_invoice_tag and at creation; return TagLimitExceeded when exceeded.

Requirements and context

• Must be secure, tested, and documented
• Prevents unbounded storage growth
• Smart contracts only (Soroban/Rust)

Suggested execution

1. Fork the repo and create a branch
   git checkout -b feature/max-tags-per-invoice
2. Implement changes
   • Implement: validation in src/invoice.rs, src/verification.rs
   • Add tests for at-limit and over-limit
   • Document in docs/contracts/invoice.md
3. Test and commit
   • Run cargo test
   • Include test output and security notes

Example commit message
feat: maximum tags per invoice enforcement with tests and docs

Guidelines

• Minimum 95 percent test coverage
• Clear documentation
• Timeframe: 96 hours

[drips-wave]

This issue has been added to the Stellar Wave Program and is worth 200 Points.

🧑‍💻 Interested in contributing? Apply to work on this issue on Drips Wave, earn points, and receive rewards.

Warning

Only applications submitted via the apply link above will be considered. Please do not apply by commenting on the issue or opening a PR directly.

🤠 Repo maintainers: You can manage this issue's Points and Complexity on your Maintainer Dashboard here. Please keep an eye on applications and respond quickly 💙

ℹ️ Learn more about Drips Wave

[abbakargarba]

@abbakargarba has applied to work on this issue as part of the Stellar Wave Program's 2nd wave.

Dear Maintainer,

I'll enforce a max tags per invoice (configurable, default 10) in add_invoice_tag and during creation, returning TagLimitExceeded when breached. Prevents unbounded storage growth. Tests cover at-limit, over-limit, and edge cases, with 95%+ coverage and clear docs.

Abbakargarba - Babax

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

[drips-wave]

Congratulations, @abbakargarba! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on February 26, 2026.

🧑‍💻 @abbakargarba: 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 issued 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 🌊

[abbakargarba]

Am on it @Baskarayelu 🌊