docs(tutorial): Testing - Debugging with Clarinet Trace

[jadonamite]

Description

This PR adds Module 19: Debugging by @jadonamite. It documents the usage of the ::trace command in the Clarinet Console to diagnose inter-contract failures.

Content Overview

• The Problem: Opaque error codes in nested contract calls.
• The Tool: Using ::trace to visualize the execution stack.
• The Analysis: How to interpret indentation and return values to find the root cause.

Checklist

• Trace output examples verified in Clarinet v2.4.
• Explanation of standard error codes (e.g., u1 for insufficient balance) included.
• Formatting follows the repository's style guide.

Related Issues

Closes # (If applicable)