Detector: Reentrancy via env.invoke_contract before effects

[Gbangbolaoluwagbemiga]

Epic: Detectors (wave 3)

Summary

Add a static-analysis detector for reentrancy via env.invoke_contract before effects.

Background & Problem

Direct invoke_contract calls preceding state writes reopen the CEI reentrancy risk.

Acceptance Criteria

• Flags invoke_contract before effects.
• No FP when effects precede.

Technical Notes

Follow the rule pattern in tooling/sanctifier-core/src/rules/ with an insta golden snapshot.

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Filed as part of the mainnet-readiness & world-class roadmap. Scope is intentionally small enough for one focused PR; comment to claim.

[odogu01]

Hello maintainer, I've gone through this issue thoroughly and can submit a pr to resolve it. Please assign

[Gbangbolaoluwagbemiga]

@odogu01, you are assigned...ensure all ci pipeline pass

[grantfox-oss]

🦊 GrantFox — @odogu01 has been assigned to this issue as part of the Official Campaign | FWC26 campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #793)
2. Your PR will be reviewed by the Centurylong maintainers

Good luck! Track your progress on GrantFox.