Angular 19 SSR cloud functions ESM build

- [ ] unable to serve/deploy ssr functions esm build artifacts with vanilla cloud functions
- [x] able to ng serve, ng build (build-angular:application), and node ./server.mjs
- [x] other functions unrelated to SSR are working (server backend) as intended

Heres my SSR setup:

universal.ts

```typescript
import { onRequest } from 'firebase-functions/v2/https';
import { render } from '../../render.js';
import express, { Request, Response, NextFunction } from 'express';
import * as server from '../../../dist/stamp-app/server/server.mjs';
export const ssrApp = express() as any;

ssrApp.use(express.static('dist/stamp-app/browser'));
ssrApp.get('*', async (req: Request, res: Response, next: NextFunction) => {
const ssr: any = await render(server, req, res, next);
res.send(ssr);
});

export const universal = onRequest(
{ maxInstances: 10, timeoutSeconds: 1200, cpu: 1, memory: '2GiB', region: ['us-central1'] },
ssrApp
);
```
render.js
```typescript
import { Request, Response, NextFunction } from "express";

export async function configServerApp(app: any, req: Request, res: Response, next: NextFunction) {
//configure app here & retrieve HTML
let template;
if (req.path === '/') {
// template = await fetch('@dist/stamp-app/browser/index.csr.html');
next();
}
template = `

`;
return template;
}
export async function render(app: any, req: Request, res: Response, next: NextFunction) {
const ssrApp = await configServerApp(app, req, res, next);
return ssrApp;
}
```

am I missing something..? thanks for any help in advance

从 universal.ts 和 render.js 开始，然后复现 ng build (build-angular:application)、node ./server.mjs 与 SSR 函数部署之间报告的差异。检查生成的 dist/stamp-app/server/server.mjs 和浏览器产物，并与原生 Cloud Functions 设置进行对照。使用 ESM 构建时，SSR 函数能够成功提供服务并完成部署，即表示完成。

由索引模型根据 Issue 内容生成。