- Restricted input formats to only FASTA and compressed FASTA files (.fasta, .fasta.gz). Removed support for FASTQ files.
- Updated the tool description and help section to accurately reflect that the tool only merges FASTA files.
- Improved the tool's clarity by ensuring it is used for its intended purpose: merging FASTA files only.

Update seqtk_mergefa.xml

"Tool merges FASTA/Q files into a FASTA output and considers the quality threshold for FASTQ files when merging."

1. Clarified the -m option to handle ambiguous bases and conflicts (e.g., N and other IUPAC codes).
2. Improved help documentation with clearer examples and explanations.
3. Refined input parameter labels for better clarity and consistency.

edited echo command line back to #echo

Suggestions from review