Add per-offering currency-denomination metadata and decimals helper for accurate display

[thlpkee20-wq]

Description

Indexers must guess display semantics for each payment token. Add denomination_symbol: Symbol and display_decimals: u32 to offering metadata so wallets and dashboards can render consistent amounts.

Requirements and context

• Must be secure, tested, and documented
• Should be efficient and easy to review
• Relevant code: Revora-Contracts/src/lib.rs
• Display decimals must be capped at 18 and compared against payment-token decimals

Suggested execution

• Fork the repo and create a branch
• git checkout -b feat/offering-denomination-metadata
• Implement changes
  • Add denomination_symbol, display_decimals to offering struct
  • Validate at register: display_decimals <= payment_token_decimals
  • Surface fields on off_reg event
• Validate security and correctness assumptions

Test and commit

• Run tests
  • cargo test --all
• Cover edge cases
  • Setting display_decimals > 18 must reject DisplayDecimalsOutOfRange
• Include test output and security notes

Example commit message

feat: add denomination_symbol and display_decimals metadata

Guidelines

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

[Keengfk]

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

I will love to work on this issue,pls 🙏 give me

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

[drips-wave]

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

🧑‍💻 @Keengfk: 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.

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