Function seq_geom_xform::xform_read_pairs_to_fifo

pub fn xform_read_pairs_to_fifo(
    geo_re: FragmentRegexDesc,
    r1: Vec<PathBuf>,
    r2: Vec<PathBuf>
) -> Result<FifoXFormData>

Given input file paths (possibly multiple sets of files) in r1 and r2, and FragmentRegexDesc geo_re, this function returns a Result<FifoXFormData>. If succesful the Ok(FifoXFormData) will contain the paths to 2 fifos (1 for each list of input read files) as well as a thread::JoinHandle. The thread::JoinHandle will be for a spawned thread that will read sequence records from the files in r1 and r2 and transform these reads in accordance with the FragmentRegexDesc provided as geo_re.
The transformed records are then written out to the fifos given in the FifoXFormData struct. Currently, all output is written in FASTA format, so any quality lines or comment lines (if the input is FASTQ) will be dropped. If an error occurs up to the creation of the spawned thread, then this function returns an Err(anyhow::Error). The spawned thread itself returns a Result<()>.