`@react-native/assets` ships Flow instead of JS

Description

The assets package is shipping flow JS directly, making it break when importing on Next.js. It should build prior to publishing and remove types.

See: https://github.com/facebook/react-native/blob/main/packages/assets/registry.js

Let me know if I should PR, though I know TypeScript and not flow. Could also migrate it.

React Native Version

0.71

Output of npx react-native info

N/A

Steps to reproduce

See https://github.com/facebook/react-native/blob/main/packages/assets/registry.js

Snack, code example, screenshot, or link to a repository

If you need a repro, you can try importing @react-native/assets in Next.js. It's pretty self-explanatory though.

Thanks!

从 packages/assets/registry.js 开始，复现从 Next.js 导入 @react-native/assets 的过程。跟踪 assets 包的发布和构建配置，然后验证已发布的入口是没有 Flow 类型的编译后 JavaScript；当从 Next.js 导入成功时即完成。