Implement comprehensive reentrancy protection across all contract entry points

[Smartdevs17]

Description

Multiple contract functions may be vulnerable to reentrancy. Add comprehensive protection using checks-effects-interactions pattern and reentrancy guards.

Acceptance Criteria

• Reentrancy guard on all mutative functions
• Cross-contract reentrancy protection
• Read-only reentrancy detection
• Formal verification of reentrancy safety
• Fuzz testing for reentrancy scenarios
• Documentation of reentrancy threat model

Technical Scope

• stellar-lend/contracts/lending/src/
• stellar-lend/contracts/hello-world/src/reentrancy.rs
• stellar-lend/contracts/hello-world/src/test_reentrancy.rs
• Edge: cross-function reentrancy, constructor reentrancy, delegate call reentrancy

[Properprogress1]

@Properprogress1 has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Can I work on this please

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Properprogress1 to this issue.

[drips-wave]

Congratulations, @Properprogress1! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @Properprogress1: 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

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