docs(tutorial): Clarity - Refactoring Solidity Loops to Fold/Map

[jadonamite]

Description

This PR adds Module 6: Clarity Logic Patterns to the tutorial series. It addresses the most common friction point for Solidity developers: the absence of for loops.

Content Overview

• Concept Mapping: Side-by-side comparison of Imperative (Loop) vs Functional (Fold) logic.
• The map Pattern: Transforming lists without mutation.
• The fold Pattern: Accumulating state and calculating totals.
• Complex State: Using tuples as accumulators for multi-variable logic.

Checklist

• Code examples are valid Clarity syntax.
• "Early Exit" limitations explicitly addressed.
• Formatting follows the repository's style guide.