Add testnet faucet hook generating deterministic test holders for integration suites

[thlpkee20-wq]

Description

Integration tests today wire up holders manually. Add a testnet-only faucet_seed_holders(offering_id, count) that allocates deterministic addresses with documented BPS distribution, so external test suites can pin against a known seed.

Requirements and context

• Must be secure, tested, and documented
• Should be efficient and easy to review
• Relevant code: Revora-Contracts/src/test_utils.rs, TESTNET_MODE.md
• Faucet must reject when testnet_mode == false

Suggested execution

• Fork the repo and create a branch
• git checkout -b feat/testnet-faucet-seed
• Implement changes
  • Gate behind is_testnet_mode() and panic on mainnet
  • Use env.crypto().sha256(seed || idx) to derive addresses
  • Emit faucet_seed events
• Validate security and correctness assumptions

Test and commit

• Run tests
  • cargo test --all
• Cover edge cases
  • Invocation outside testnet must error TestnetOnly
• Include test output and security notes

Example commit message

feat: add testnet-only faucet_seed_holders for integration suites

Guidelines

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

[MorsH14]

@MorsH14 has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

I'd love to work on this issue

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[drips-wave]

Congratulations, @MorsH14! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 30, 2026.

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