HttpResponseredirected Property Support

This commit adds support for the Fetch API's redirected property in HttpResponse and HttpErrorResponse when using HttpClient with the withFetch provider.

This change builds on the functionality introduced in#62315, which added support for passing the redirect option to the Fetch API. With redirects now configurable, exposing the redirected property provides developers with a way to determine if a response was the result of a redirect, further aligning HttpClient's behavior with the native Fetch API and enhancing observability of request flow

The Change Includes:

• Addedredirected property toHttpResponse andHttpErrorResponse classes
• UpdatedFetchBackend to capture and forward theredirected flag from the native fetch response
• Maintains consistency with the Fetch API specification
• Added unit tests to ensure the property is correctly captured and exposed

Motivation / Use Cases

Theredirected property provides valuable information about whether the response was the result of a redirect:

• Security: Detect when requests have been redirected, which is important for security-sensitive applications
• Analytics: Track redirect behavior for performance monitoring and debugging
• Conditional Logic: Implement different handling based on whether a response was redirected
• API Compliance: Maintain consistency with the native Fetch API behavior

Examples of New Usage

Basic Redirect Detection

import{HttpClient}from'@angular/common/http';constructor(privatehttp:HttpClient){}// Detect if the response was redirectedthis.http.get('/api/data',{observe:'response'}).subscribe({next:(response)=>{if(response.redirected){console.log('Response was redirected');console.log('Final URL:',response.url);}}});

Conditional Logic Based on Redirects

// Handle different scenarios based on redirect statusthis.http.get('/api/user-profile',{observe:'response'}).subscribe({next:(response)=>{if(response.redirected){// User might have been redirected to login pagethis.handlePossibleAuthRedirect(response);}else{// Direct response, process normallythis.processUserProfile(response.body);}}});