Default annual renewal to business created date.

Backfill null renewals from created_at and use now when create omits the date.

Co-authored-by: Cursor <cursoragent@cursor.com>

database/migrations/074_backfill_annual_renewal_from_created.sql

@@ -0,0 +1,5 @@
+-- Default annual renewal to business created date when unset.
+
+UPDATE businesses
+SET annual_renewal_at = created_at
+WHERE annual_renewal_at IS NULL;