[Data] Import Bat Conservation International (BCI) reference set from S3 as initial vetting dataset

[aashish24]

Background:
Use Bat Conservation International (BCI) reference files currently stored in S3 as the initial dataset for vetting and review in BatAI.

Requirements (Data Task Checklist):

• Ingest the Bat Conservation International (BCI) reference set from S3 into BatAI.
• Register the dataset as a shared vetting dataset.
• Ensure the dataset is read-only and immutable for reviewers.
• Confirm that all reviewers see the same files and file counts.

Acceptance criteria:

• The Bat Conservation International (BCI) reference dataset is available in BatAI.
• The dataset contents are consistent across all reviewers and sessions.