feature request: single assets in i18n builds

### Command

build

### Description

Hi.
Currently angular just copy assets folder to every localized build. This leads to enormous dist size (in my case every locale with assets weigths 180MB, which can be multiplied by 15 locales).

### Describe the solution you'd like

My proposal is to put assets folder in root directory, instead of copying it inside every built locale, and symlink it inside every locale. This will give us better build times, and also will fix issues where developers use absolute urls to assets, eg:

```

```

My solution will give developers a way to use localized builds in mobile apps development (with capacitor for example; for now it’s strange to publish mobile app which weights over 2gb), better build times (no need to copy assets to every locale), better deploy times (transfer 180mb instead of 2.7GB)

### Describe alternatives you've considered

Currently, the only issue i encounter, is absolute path usage (described it in my example with img src). I make symlink to get this working:

/en/assets -> /assets

从构建命令开始，跟踪 assets 如何被复制到每个本地化构建中。将当前按 locale 生成的输出与提议的根级 assets 和 locale symlink 进行比较；当 assets 不再重复，且绝对 /assets URL 继续正常工作时，即视为完成。

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