P22.1 of Stage 22 materialization layer infrastructure. Adds explicit
CREATE EXTENSION migration so clean environments can run `migrate` end-to-end
without ops manual setup, then creates the first continuous aggregate
orders_daily_by_created (day-bucketed, grouped by company/platform/store)
with WITH NO DATA. Five composite indexes cover the high-frequency query
patterns documented in docs/data_query.md. P22.2/P22.3 will add the
by-paid view, refresh policy and historical backfill on top.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
