Detect Unsafe Signature Recovery Usage

[mijinummi]

🧠 Concept

Detect insecure ecrecover implementations.

⚠️ Problem

Improper signature recovery may allow forgery.

📁 Implementation Scope

• rules/security/signatures/

✅ Requirements

• Detect unsafe ecrecover usage
• Validate malleability protections

🎯 Acceptance Criteria

• Unsafe signature recovery detected