feat(@angular/ssr): support the standard Forwarded header by alan-agius4 · Pull Request #33406 · angular/angular-cli

This commit adds support for the standard RFC 7239 `Forwarded` header in the Angular SSR request parsing and validation layers.

Previously, only non-standard `x-forwarded-*` headers were supported for resolving proxy-forwarded protocols, hosts, and ports. With this change:
- A new `parseForwardedHeader` utility is added to parse standard `Forwarded` header parameters (such as `host` and `proto`), correctly handling quoted values and escaped characters.
- In `createRequestUrl`, if the `Forwarded` header is trusted (via `trustProxyHeaders` configuration), its `host` and `proto` parameters are extracted and take precedence over corresponding `x-forwarded-host` and `x-forwarded-proto` headers.
- Request validation is updated to verify the validity of `Forwarded` host and proto parameters.
- Request sanitization is updated to scrub or retain the `Forwarded` header based on the configured trusted proxy headers.

Reference: https://developer.mozilla.org/en-US/docs/Web/HTTP/Reference/Headers/Forwarded