Add database connection

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: 705f2157-ef97-4fbd-89e4-8c7f2ecaea90
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/7ed01c5f-a82d-405a-b728-b2e3d127c60c/17da3fa6-3077-45d0-a6c3-928381e9f454.jpg

server/db.ts

@@ -0,0 +1,15 @@
+import { Pool, neonConfig } from '@neondatabase/serverless';
+import { drizzle } from 'drizzle-orm/neon-serverless';
+import ws from "ws";
+import * as schema from "@shared/schema";
+
+neonConfig.webSocketConstructor = ws;
+
+if (!process.env.DATABASE_URL) {
+  throw new Error(
+    "DATABASE_URL must be set. Did you forget to provision a database?",
+  );
+}
+
+export const pool = new Pool({ connectionString: process.env.DATABASE_URL });
+export const db = drizzle({ client: pool, schema });