Bug/is user code

[waldo121]

Summary

Fix bug in is_user_code

Related Issue

Closes #44

Type of Change

• Bug fix
• New feature
• Refactor
• Documentation update
• CLI behavior change

What Changed

In is_user_code:

• normalized paths
• Add handling for special paths such as:

1. virtual environments
2. stdlib
3. symlinked code

• new unit tests for tracer.py

Validation

• Run test

pytest tests/test_tracer.py

Checklist

• The code follows style conventions.
• I added unit tests for the new functionality.
• CI (GitHub Actions) is green.
• I updated documentation/README when needed.