Add composite indexes on advertising_campaign_registrations(user_id,
created_at) and transactions(user_id, type, is_completed, amount_kopeks)
to enable index-only scans. Uses CREATE INDEX CONCURRENTLY for zero
downtime. Also enable transaction_per_migration in Alembic env.py.
Only apply alembic.ini logging config when root logger has no handlers
(CLI mode). When running programmatically, structlog is already configured
and fileConfig would replace its handlers, breaking all logging.
Fringg