[Docs] Create "How to Document Your Contract" Guide

[mijinummi]

Title: [Docs] Create "How to Document Your Contract" Guide

📝 Description

We need to help developers understand how to make the most of SpecDoc. This guide will explain how to prepare their contracts for the best documentation experience.

🎯 Goal

Write a docs/best-practices.md file that explains how to use NatSpec (Solidity) or Doc-comments (Rust) to improve the generated output.

✅ Requirements

• Explain how SpecDoc pulls "Description" text from code comments.
• Provide a "Before vs. After" example of a well-documented contract.
• List supported wallet integrations (Freighter, MetaMask).