Michael Myaskovsky via Elementary: Simplify customers model SQL

[elementary-data-local]

Summary

This PR simplifies the customers model by changing it to directly select all columns from stg_customers, removing the complex CTEs and aggregations.

Changes

• Before: Complex model with multiple CTEs joining customers, orders, payments, and signups data
• After: Simple select * from {{ ref('stg_customers') }}

Impact

⚠️ Breaking Change: This significantly changes the customers table structure:

• Keeps: customer_id, first_name, last_name (from stg_customers)
• Removes: All derived metrics like customer_lifetime_value, number_of_orders, first_order, most_recent_order, customer_email, signup_date

Testing

Please ensure:

1. Downstream models and BI reports are updated to accommodate the new structure
2. Any dependencies on removed columns are addressed
3. dbt run and tests pass after this change
   
   Created by: [email protected]