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)

drizzle.config.ts

@@ -0,0 +1,12 @@
+import { defineConfig } from "drizzle-kit";
+
+export default defineConfig({
+  schema: "./lib/db/schema.ts",
+  out: "./lib/db/migrations",
+  dialect: "postgresql",
+  dbCredentials: {
+    url:
+      process.env.DATABASE_URL ??
+      "postgresql://postgres:postgres@localhost:5432/moh_sass?schema=public",
+  },
+});