add Preprocessing for Group Assignment and Co-Assembly section

[mthang]

@bebatut
This "Preprocessing for Group Assignment and Co-Assembly Workflow" section is created as part of the Assembly of metagenomic sequencing data tutorial for FAIRyMAGs Hybrid Hackathon 2025: Optimising Metagenomics Assembled Genomes building.

The changes are made based on this workflow https://github.com/usegalaxy-eu/FAIRyMAGs/blob/main/Workflows/Group-Co-assembly.md.

• added metadata table
• create a collection using the paired-end dataset from the Assembly of metagenomic sequencing data tutorial
• unzip the collection
• Tag the forward and reverse dataset collection with the information defined in the metadata table
• create a zip collection using the Tag collection (i.e forward and reverse end)
• Apply rules to the zip collection to reorganize the collection based on group information defined in the metadata table
• Concatenate the collection by stand

TODO:

• reviewing the newly created "Preprocessing for Group Assignment and Co-Assembly Workflow" section is required