chore(db): finish Prisma cutover to Drizzle Kit tooling

Move CMS SQL to drizzle/migrations, drop prisma packages/schema, wire drizzle-kit scripts, and regenerate schema names from src/db/schema.ts.

Co-authored-by: Cursor <[email protected]>

drizzle/migrations/0002_users_2fa.sql

@@ -0,0 +1,6 @@
+-- Fortify-style 2FA columns on the emulator users table. Idempotent (MariaDB).
+-- AtomCMS installs already have these; this only adds them when missing.
+ALTER TABLE users
+  ADD COLUMN IF NOT EXISTS two_factor_secret TEXT NULL,
+  ADD COLUMN IF NOT EXISTS two_factor_recovery_codes TEXT NULL,
+  ADD COLUMN IF NOT EXISTS two_factor_confirmed_at TIMESTAMP NULL;