Re-implement POST /data endpoint to accept file arrays

[MitchellShiell]

Problem: Lyric version 0.9.1 removed file array inputs (CSV and TSV) from the request body and replaced it with raw json data. Although this is more machine readable it is not the native/common format data submitters interact and store there tabular data in.

Expected Deliverable: support both input file arrays and JSON in the request body of the POST /data endpoint

Important Considerations: xSV parsing brings added complexity and potential edge cases to data submission that requires further consideration, particularly around separators (@justincorrigible please provide added context here or below as a comment)

[justincorrigible]

the aforementioned parsing complexity revolves around the separators, trimming, different blankspace formats, etc.
for reference and additional detail, this is a good centralized spot https://github.com/csvspecs/awesome-csv