Write ADR for NFT invoice representation

[Levi-Ojukwu]

Description:

The NFT invoice representation is a significant design decision that needs documentation.

Why it matters: NFTs enable secondary markets and composability.

Acceptance Criteria:

• Create docs/adr/adr-007-nft-invoice-representation.md
• Cover motivation, design, trade-offs

Relevant Files: docs/adr/, contracts/invoice_liquidity/src/nft.rs

---

[CodedBay]

@CodedBay has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Dear maintainer,

I would love to take on this issue. I have solid experience working with smart contracts, state validation, and writing robust test suites, and frontensd and I am confident I can implement this cleanly and submit a clean, mergeable PR.

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

[Samuel1505]

@Samuel1505 has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

I would like to work on this issue, kindly assign me

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Samuel1505 to this issue.

[drips-wave]

Congratulations, @Samuel1505! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on July 30, 2026.

🧑‍💻 @Samuel1505: 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 🌊

[drips-wave]

This issue has been completed by @Samuel1505 as part of the Stellar Wave Program's 7th Wave 🥳

😎 @Samuel1505: 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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