Add a protocol-config bounds enforcement test matrix for set_protocol_config and set_fee_config in init.rs

[Baskarayelu]

📋 Description

Admin config entrypoints in quicklendx-contracts/src/init.rs/lib.rs — set_protocol_config (min invoice amount, max due-date days, grace-period seconds) and set_fee_config (fee bps) — must respect bounds: MAX_FEE_BPS = 1000, MAX_DUE_DATE_DAYS = 730, MAX_GRACE_PERIOD_SECONDS. Prior work added init invariants and a dry-run preview, but a focused bounds-enforcement matrix asserting each parameter is clamped/rejected at its exact limit is not present.

Why this matters: config bounds are the guardrails on protocol-critical economics. A fee bps above the cap would let an admin overcharge every settlement; a grace period beyond the max would strand investor remedy. Pinning rejection at exactly the boundary for each parameter makes the guardrails provable, not assumed.

🎯 Requirements & Context

Functional requirements

• Add quicklendx-contracts/src/test_config_bounds_matrix.rs asserting set_fee_config accepts MAX_FEE_BPS and rejects MAX_FEE_BPS + 1 with InvalidFeeBasisPoints.
• Assert set_protocol_config accepts each parameter at its max and rejects one over (MAX_DUE_DATE_DAYS, MAX_GRACE_PERIOD_SECONDS, and the min-invoice-amount lower bound).
• Assert non-admin callers are rejected before any state change.
• Assert accepted values are actually persisted and readable via the corresponding getters.

Context & constraints

• Reuse fixtures from test_init.rs and test_init_invariants.rs.
• Test-only; document any unclamped parameter as a finding.
• Soroban SDK 25.1.1.

🛠️ Suggested Execution

1. Fork & branch

git checkout -b test/config-bounds-matrix

2. Implement changes

• Build the at-limit / over-limit matrix for each parameter and the persistence assertions.
• Doc-comment each bound under test.

3. Test & commit

cargo test -p quicklendx-contracts test_config_bounds_matrix -- --nocapture

• Edge cases: fee bps of exactly 0 (min); min invoice amount at the lower bound; max due-date at exactly 730; all parameters set in one call.

Example commit message

test(governance): add config-bounds enforcement matrix for set_protocol_config/set_fee_config

Pins accept-at-max / reject-over-max for fee bps, due-date, grace period, and min amount.

✅ Acceptance Criteria & Guidelines

Requirement	Target
At-limit accept / over-limit reject matrix	Required
Non-admin rejected before mutation	Required
Accepted values persisted + readable	Required
Coverage of config branches	≥ 95%
Docs + doc comments	Required
cargo test + cargo clippy clean	Required
Timeframe	96 hours from assignment

💬 Community & Support

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Please drop a note in the channel when you pick this up so we can avoid duplicate work and unblock you fast. Clear communication during the PR keeps the review fast and friction-free. 🚀

[Kuhai9801]

I’d like to work on this.

I have experience with smart-contract security testing and bug bounty-style boundary/invariant checks. I’ll add a focused bounds-enforcement test matrix for set_protocol_config and set_fee_config, covering exact limit values and out-of-range rejection for fee bps, due-date days, and grace-period seconds.

[grantfox-oss]

🦊 GrantFox — @Kuhai9801 has been assigned to this issue!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #1346)
2. Your PR will be reviewed by the QuickLendX maintainers

Good luck! Track your progress on GrantFox.

[grantfox-oss]

🎉 This issue has been marked as completed on GrantFox!

@Kuhai9801's PR #1382 was approved and merged by @Baskarayelu.

🏆 @Kuhai9801: You earned 35 FoxPoints for this contribution! Your current tier: Explorer (328 total points). Track your full progress on GrantFox.

👏 Great work, @Kuhai9801! Keep contributing to QuickLendX.