Add logic to copy historical data

[vish-cs]

No description provided.

[gemini-code-assist]

Code Review

This pull request introduces a feature to ingest historic data from GCS into the versioned output directory, controlled by a new configuration flag ingest_historic_data. However, the changes also comment out the virtual environment creation (_create_venv), replacing it with a dummy process and sys.executable, which will bypass dependency installation and likely cause runtime failures. Additionally, the GCS blob listing logic for historic data should be refined to use a slash-terminated prefix to prevent matching unintended directories and to simplify path parsing.