Handle ingest TSV path inputs

[Ulthran]

Summary

• load TSV inputs from file paths in ingest_from_tsvs to support CLI usage
• add regression coverage ensuring isolate ingestion works when given path strings

Testing

• PYTHONPATH=. pytest tests/test_ingest.py

---

Codex Task

[Copilot]

Pull request overview

This PR enhances the ingest_from_tsvs function to accept file paths (strings or Path objects) in addition to DataFrames, enabling CLI usage where file paths are passed as command-line arguments. Previously, the function only accepted DataFrames, requiring callers to manually load TSV files.

Key Changes:

• Added _load_dataframe helper function to convert path inputs to DataFrames
• Updated all data parameters in ingest_from_tsvs to load from paths if provided
• Added regression test verifying path string inputs work correctly

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
marc_db/ingest.py	Adds Union import, implements _load_dataframe helper function, and applies it to all 6 data parameters in ingest_from_tsvs
tests/test_ingest.py	Adds test case verifying ingest_from_tsvs accepts string paths for the isolates parameter

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.