Add --reports argument to Index CLI

[junho85]

Description

Implements --reports argument to the Index CLI, allowing users to specify a dedicated directory for reports. This enhances the flexibility of the pipeline configuration and decouples report directory management from output directory settings.

The --reports argument was mentioned in the documentation at https://github.com/microsoft/graphrag/blob/dda4edd0fd2ad2665045a1689f14e68a198d6a7a/docsite/posts/index/2-cli.md?plain=1#L28, but had not been implemented.

Related Issues

Proposed Changes

• Implements --reports argument to the CLI

Checklist

• [x] I have tested these changes locally.
• [x] I have reviewed the code changes.
• [ ] I have updated the documentation (if necessary).
• [ ] I have added appropriate unit tests (if applicable).

Additional Notes