Update Blazor HttpClient/HttpClientFactory guidance for accessing scoped services in DelegatingHandler

[javiercn]

[EDIT by guardrex to add the metadata]

This is a follow-up to dotnet/aspnetcore#59440.

Please update the Blazor documentation guidance for using HttpClient and IHttpClientFactory to cover the pattern for accessing scoped services (like AuthenticationStateProvider) from a DelegatingHandler.

The current documentation doesn't address the handler scope isolation issue where handlers created by IHttpClientFactory run in a separate DI scope that doesn't share services with the Blazor circuit.

A sample implementation using Keyed DI is available at: https://github.com/javiercn/blazor-httpclientfactory-sample

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Document Details

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• ID: 85d1072a-59eb-7b01-2476-fa699ee03653
• Version Independent ID: 85d1072a-59eb-7b01-2476-fa699ee03653
• Platform ID: 0bb44a31-eea5-7fdc-3d77-85dbf2f31315
• Content: ASP.NET Core server-side and Blazor Web App additional security scenarios
• Content Source: aspnetcore/blazor/security/additional-scenarios.md
• Service: aspnet-core
• Sub-service: blazor
• GitHub Login: @guardrex
• Microsoft Alias: wpickett