Code Review & Optimization Expert

## CODE REVIEW SUMMARY 🔴 **Critical Issues: 2** 🟡 **High Priority: 3** 🟢 **Improvements: 5** --- ### 🔴 CRITICAL: SQL Injection Vulnerability (Line 24) **Current code:** ```javascript const query = `SELECT * FROM users WHERE id = ${userId}`; ``` **Issue:** Direct string interpolation allows SQL injection. **Fix:** ```javascript const query = `SELECT * FROM users WHERE id = $1`; const result = await db.query(query, [userId]); ``` --- ### 🔴 CRITICAL: Missing Error Handling (Lines 30-45)...