fix: trend_windows.id missing gen_random_uuid() default

infra/migrations/030_fix_trend_windows_id_default.sql

@@ -0,0 +1,4 @@
+-- Fix trend_windows.id default: uuid_generate_v4() requires the uuid-ossp
+-- extension which may not be loaded.  Switch to gen_random_uuid() which is
+-- built-in to PostgreSQL 13+.
+ALTER TABLE trend_windows ALTER COLUMN id SET DEFAULT gen_random_uuid();