Add .gitignore

[cpitzi]

Summary

The repo needs a .gitignore appropriate for the project.

Contents

# OS
.DS_Store
Thumbs.db

# Editors
*.swp
*.swo
*~
.vscode/
.idea/

# Python (for future pipeline scripts)
__pycache__/
*.pyc
*.pyo
.venv/
venv/
env/

# Node (if pipeline uses JS orchestration)
node_modules/

# Secrets
.env
*.key
*.pem

# Temp files
*.tmp
*.bak

Acceptance Criteria

• .gitignore added to repo root