Migrate to local PG & Update Solana Checkout

lib/db.ts

@@ -0,0 +1,10 @@
+import { Pool } from 'pg';
+
+const pool = new Pool({
+  connectionString: process.env.DATABASE_URL,
+});
+
+export const db = {
+  query: (text: string, params?: any[]) => pool.query(text, params),
+  pool,
+};