inventions...almost working

apps/api/migrations/0003_invention_featured.sql

@@ -0,0 +1,13 @@
+-- Break `IsFeatured` out of the invention JSON blob into a queryable generated
+-- column, so the featured feed (`/api/inventions/v1/featured`) filters in SQL on
+-- an index instead of parsing every published invention in memory. Generated from
+-- src/inventions-db.ts (SCHEMA_DDL) — keep in sync.
+--
+-- SQLite allows ALTER TABLE ADD COLUMN only for VIRTUAL generated columns (a
+-- STORED one would need rewriting existing rows), which is what we want anyway:
+-- the value stays derived from `data`, so nothing can drift out of sync with it.
+-- json_extract of a JSON `true` is 1, so the column reads 1/0.
+
+ALTER TABLE invention
+  ADD COLUMN is_featured INTEGER GENERATED ALWAYS AS (json_extract(data, '$.IsFeatured')) VIRTUAL;
+CREATE INDEX IF NOT EXISTS idx_invention_featured ON invention (is_featured);