Support for Multi-Domain Locale Detection in Angular SSR

### Description

Currently, Angular SSR does not provide built-in functionality to detect the domain in a multi-domain setup and serve the appropriate localized version of the application. This feature would allow Angular SSR to dynamically render pages with the correct locale based on the domain.

**Use Case**:
- Applications serving different localized versions (e.g., `example.com`, `fr.example.com`, `example.de`) need SSR to serve the appropriate locale.
- Example:
- `example.com` → English content
- `fr.example.com` → French content
- `example.de` → German content

### Describe the solution you'd like

Allow SSR to use the detected domain to select the corresponding locale configuration. Which simplifies multi-language deployment without relying on path-based locales (e.g., `/en`, `/fr`).

### Describe alternatives you've considered

_No response_

Begin by locating Angular SSR's locale configuration and request/domain handling entry points; the issue names no files or tests. Done means SSR selects the appropriate locale for example.com, fr.example.com, and example.de without relying on path-based locale segments, with coverage for the supported mappings.

Written by the indexing model from the issue text.