Add UseDefaultServiceProvider extension methods for WebAssembly host builder

[rolandVi]

Add UseDefaultServiceProvider extension methods for WebAssembly host builder

Summary

This pull request enhances the WebAssemblyHostBuilder by introducing support for customizable service provider options.

Problem Solved

Previously, circular DI dependencies in Blazor WebAssembly apps would cause the browser to hang with no error message. Now developers get validation errors at build time instead of runtime hangs, especially in development environments.

Changes Made

• Added WebAssemblyHostBuilderExtensions class with two UseDefaultServiceProvider overloads
• Added UseServiceProviderOptions method to WebAssemblyHostBuilder
• Modified constructor to enable ValidateOnBuild = true by default in development environment
• Added tests for the new functionality

Public API updates:

• Updated PublicAPI.Unshipped.txt to include the new UseServiceProviderOptions method and UseDefaultServiceProvider extension methods

Test improvements:

• Added tests to verify the functionality of UseDefaultServiceProvider
• Added tests to ensure correct behavior with circular dependencies

API Usage

// Simple configuration
builder.UseDefaultServiceProvider(options => 
{
    options.ValidateOnBuild = true;
});

// Environment-aware configuration  
builder.UseDefaultServiceProvider((env, options) =>
{
    options.ValidateOnBuild = env.IsDevelopment();
});

Fixes #43866

[javiercn]

Looks great!