Detect Dynamic Array Deletion Inefficiencies

# 🧠 Concept  
Detect expensive dynamic array deletions.

## ⚠️ Problem  
Improper deletions waste gas.

## 📁 Implementation Scope  
- `rules/optimization/arrays/`

## ✅ Requirements  
- Detect shifting operations  
- Suggest swap-and-pop  

## 🎯 Acceptance Criteria  
- [ ] Inefficient deletions detected  