Add Santander customer data for analysis

[devin-ai-integration]

Summary

Added Santander customer dataset to the data/ directory in both Excel and CSV formats. The dataset contains 500 customer records with 24 columns including customer demographics, account information, and behavioral flags.

Dataset overview:

• 500 rows × 24 columns
• Fields include: customer_id, personal info (name, email, phone, DOB, age, gender, address), account details (type, number, sort code, balance), income bracket, credit score, and digital engagement flags
• No missing values
• Average balance: £24,493 | Average credit score: 682 | Age range: 18-85

Review & Testing Checklist for Human

• Verify this is synthetic/sample data appropriate for committing to the repository (contains PII-like fields: names, emails, phone numbers, addresses)
• Confirm the CSV export accurately represents the Excel source data
• Check if these data files should be added to .gitignore instead of being tracked in version control

Notes

Data was downloaded from S3 (s3://devin-workshop/santander_customers.xlsx) using AWS credentials and converted to CSV using pandas.

Requested by: Joao Esteves (@joao-cognition)
Devin session: https://app.devin.ai/sessions/024c404ba3704080995b2434d56195d9

[devin-ai-integration]

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