Add fix for generating embeddings

[caufieldjh]

This pull request enhances the embedding export functionality by ensuring that embeddings are correctly included in CSV exports when requested, and adds comprehensive test coverage for this behavior. The changes also improve the reliability of the export process and update related tests to check for the correct function calls and output.

Embedding Export Improvements:

• The export_embeddings_to_csv function in embedding_generation_utils.py now includes embeddings in the export when include_embeddings=True is specified, by passing the appropriate argument to the store's find method.
• The CLI's generate_embeddings function now always sets include_embeddings=True when exporting embeddings, ensuring that the exported CSV contains embedding data.

Testing Enhancements:

• The test for CLI embedding export in test_cli_embeddings.py now asserts that export_embeddings_to_csv is called with include_embeddings=True, verifying the correct function call signature.
• A new test in test_embedding_generation.py verifies that embeddings are included in the CSV output when requested, and that the output has the expected format and content.