veupath gene models as workflow inputs

this was a thing it seemed the ppl i talked to at mpm responded well to. think we could probably grab gff from their downloads portal at some interval, host at ucsc..

No files, tests, or entry points are named. Start by locating how workflow inputs and external gene-model data are represented; the issue needs an agreed scope for retrieving GFF files, refreshing them, hosting them at UCSC, and exposing them as inputs before implementation can be considered complete.

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