Add AI DEV Node deployment foundation

server/db/pool.ts

@@ -0,0 +1,23 @@
+import pg from 'pg';
+import { requireDatabaseUrl } from '../config/env.js';
+
+let pool: pg.Pool | undefined;
+
+export function getPool(): pg.Pool {
+  pool ??= new pg.Pool({
+    connectionString: requireDatabaseUrl(),
+  });
+  return pool;
+}
+
+export async function query<T extends pg.QueryResultRow = pg.QueryResultRow>(
+  text: string,
+  params?: unknown[],
+): Promise<pg.QueryResult<T>> {
+  return getPool().query<T>(text, params);
+}
+
+export async function closePool(): Promise<void> {
+  await pool?.end();
+  pool = undefined;
+}