Joost Boonzajer Flaes via Elementary: Fix: Convert historical_orders monetary amounts from cents to dollars

[joostboon]

Problem\n\nThe historical_orders model outputs all monetary columns (amount, credit_card_amount, coupon_amount, bank_transfer_amount, gift_card_amount) in cents, while real_time_orders already converts them to dollars using the cents_to_dollars macro.\n\nSince the orders model unions both tables, this creates a 100× scale mismatch in the amount column, which propagates through:\norders → customer_conversions → attribution_touches → cpa_and_roas\n\nThis causes the RETURN_ON_ADVERTISING_SPEND anomaly test to fail continuously (incident with 71+ failure events since Oct 2025).\n\n## Fix\n\n- historical_orders.sql: Apply cents_to_dollars() macro to all monetary columns, matching the pattern in real_time_orders.\n- real_time_orders.sql: Add a clarifying comment (no logic changes).\n\n## Related\n\n- Incident: column_anomalies - Average on cpa_and_roas.RETURN_ON_ADVERTISING_SPEND (HIGH severity)\n- JIRA: JSO-1"

Created by: joost@elementary-data.com