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]>

scripts/apply-migrations.ts

@@ -6,7 +6,7 @@ import { mysqlConnectionUrl } from "./db-url";
 import { splitSqlStatements } from "./sql-statements";
 
 const __dirname = dirname(fileURLToPath(import.meta.url));
-const MIGRATIONS_DIR = resolve(__dirname, "../prisma/migrations");
+const MIGRATIONS_DIR = resolve(__dirname, "../drizzle/migrations");
 const TRACKING_TABLE = "cms_migrations";
 
 interface MigrationFile {