Protect against reentrancy attacks in smart contracts

[Smartdevs17]

Description

Smart contract functions that transfer tokens and update state are susceptible to reentrancy attacks. Implement checks-effects-interactions pattern and reentrancy guards.

Acceptance Criteria

• Reentrancy guard modifier on all mutative functions
• Checks-effects-interactions pattern verified across all functions
• Cross-contract reentrancy protection
• Fuzz testing for reentrancy scenarios
• Formal verification of reentrancy safety
• Emergency circuit breaker for reentrancy detection

Technical Scope

• contracts/src/lib.rs
• contracts/src/security_properties.rs
• contracts/test/foundry/
• Edge: read-only reentrancy, cross-function reentrancy, constructor reentrancy

[TUPM96]

Submitted PR: #411

It adds a storage-backed reentrancy guard, emergency pause/status surface, and runnable security-property coverage for guarded mutation flows.

Verification completed locally:

• cargo fmt
• cargo test (15 passed)
• cargo build
• git diff --check

Foundry was not run because forge is not installed in this local PATH.

[abdulqoyumadegoke]

@abdulqoyumadegoke has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

I would like to work on this task

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

[Jumongweb]

@Jumongweb has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hi maintainer, i will like to solve this issue

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