Support Excel File Upload in Data Analysis Agent

Description:

The current implementation of the data-analysis-agent in community/data-analysis-agent only allows CSV files for upload and analysis:

file = st.file_uploader("Choose CSV", type=["csv"])

However, many data analysts frequently work with Microsoft Excel files (.xlsx or .xls) in addition to CSV. To enhance usability and broaden adoption, the file uploader should support both CSV and Excel formats.

Proposed Enhancement:

Update the st.file_uploader line to accept both csv and xlsx file types.

Add logic to detect the file extension and load using either:

pd.read_csv(file) for CSV

pd.read_excel(file) for Excel

Benefit:

This change will make the tool more flexible for data analysts and users who prefer working with Excel formats, which are common in business and research environments.

In community/data-analysis-agent, find the Streamlit file uploader and the surrounding data-loading entry point. Read how the current CSV upload is handled, then verify the uploader accepts CSV and Excel extensions and that each format uses the corresponding pandas loader. Done means both CSV and Excel files can be uploaded and analyzed without changing existing CSV behavior.