PFCI 0.1.0

• Initial CRAN submission.
• Implements the two-stage Penalized Fast Causal Inference (PFCI) algorithm combining graphical lasso screening with FCI orientation.
• Core functions: pfci_fit(), pfci_metrics(), plot_pag(), simulate_pfci_toy(), simulate_with_latent(), metrics_with_latent().
• Accompanies Pal, Ghosh, and Yang (2025), Annals of Applied Statistics, doi:10.48550/arXiv.2507.00173.