Remove trace artifacts and temporary files

These files were accidentally included in the previous commit:
- traces/ directory (both root and advanced_source/)
- Screenshot PNG files
- CUDA_GRAPH_TUTORIAL_README.md

These are build artifacts and temporary files that should not be
committed to the repository.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: yushangdi