Add gfastats module (structural assembly statistics)

[Daniel-VM]

Description of feature

Description

Add a module for gfastats, a tool that parses assembly FASTA/GFA files and produces detailed metrics, including circularity status, which is helpful in bacterial genome projects.

Goal

• Build a module that runs gfastats on FASTA files
• Report standard metrics (N50, circularity, etc.) and check whether output stats can be added to MultiQC
• Include documentation