Migrate historic Label Studio and "needs identification" sources

[josh-chamberlain]

Context

• pursuant to Data source ID: Retool interface #126: We now have data labeling infrastructure and an interface in Retool.
• We used to do labeling in Label Studio, and we still have some labeled sources there (~500 IIRC).
• We have ~1900 data sources where approval_status = "needs identification" because they are either missing record_type, agency_described, or both
  • they were only stored there for temporary safekeeping

Requirements

• rescue the labeled data from Label Studio
  • reject labels where there are multiple annotators but not 100% agreement
• fill in our new db, as though we used the retool interface to make those labels
• bring in the "needs identification" sources (as a special manually-created batch?), and set them up to run through the official labeling process.
  • delete the sources; they can be created anew when labeled