REFACTORED - migrate the data layer from Prisma to Drizzle (unify the stack)

- Add lib/db (Drizzle schema: 7 tables + 6 enums + relations, postgres.js client),
  drizzle.config.ts, lib/db/enums.ts (Prisma-compatible enum objects)
- Rewrite all 14 app consumers + 4 admin components to Drizzle
- Move the test DB layer to Drizzle + in-process PGlite; convert all 8 integration
  test files + factories (371 tests green)
- Remove Prisma: deps, prisma/ schema+migrations, lib/prisma.ts, Dockerfile prisma
  generate; wire db:generate/migrate/push/studio to drizzle-kit; update Makefile
- Preserve the old seed as scripts/legacy-prisma-seed.cjs (needs a Drizzle rewrite)

app/_admin/site-settings/brand/page.tsx

@@ -1,4 +1,4 @@
-import { MediaKind } from "@prisma/client";
+import { MediaKind } from "@/lib/db/enums";
 import { redirect } from "next/navigation";
 
 import { MotionFade } from "@/components/motion-fade";