feat: migrate from a.cli to article-cli

[prudhomm]

Summary

Migrate the presentation.template.d repository from the legacy a.cli bash script to the modern article-cli Python package.

Changes

New Files

• pyproject.toml - article-cli configuration with project type, XeLaTeX engine, and fonts settings

Updated Files

• .github/workflows/latex.yml - Updated CI/CD workflow to use article-cli commands:
  • article-cli setup instead of bash a.cli setup
  • article-cli install-fonts instead of bash a.cli installfonts
  • article-cli compile --engine xelatex for compilation
• README.md - Updated documentation with article-cli commands and usage examples

Benefits

• Centralized tool management via PyPI package
• Consistent commands across all NumPEx LaTeX projects
• Better maintainability (Python vs bash)
• Access to new features: theme installation, font management, etc.

Related

• article-cli v1.3.0: https://pypi.org/project/article-cli/

Closes #9