[WIP] Fix IServiceProvider resolution for DataAnnotations validation

[Copilot]

Thanks for assigning this issue to me. I'm starting to work on it and will keep this PR's description up to date as I form a plan and make progress.

Original prompt

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This section details on the original issue you should resolve

<issue_title>Wire up IServiceProvider when validating DataAnnotations attributes on Options</issue_title>
<issue_description>### Describe the bug
App was unable to resolve IWebHostEnvironment from ValidationContext when validating options with custom Required attribute inside Configure method.

To Reproduce

IWebHostEnvironment not resolving, when trying to create a custom validation attribute to make something required only in Production environment.

Relevant code snippets

    public class DemoOptions
    {
        [RequiredInProd]
        public string FooBar { get; set; }
    }

    public class RequiredInProd : RequiredAttribute
    {
        protected override ValidationResult IsValid(object value, ValidationContext validationContext)
        {
            //this errors
            var env = validationContext.GetRequiredService<IWebHostEnvironment>();
            return ValidationResult.Success;
        }
    }
//Startup.cs methods
public void ConfigureServices(IServiceCollection services)
        {
            services.AddOptions<DemoOptions>()
                .Bind(Configuration.GetSection(nameof(DemoOptions)))
                .ValidateDataAnnotations();
        }

        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            //this line works fine and IWebHostEnvironment is resolved.
            var envFromServices = app.ApplicationServices.GetRequiredService<IWebHostEnvironment>();
            //this errors when trying to resolve IWebHostEnvironment inside Attribute methods
            _ = app.ApplicationServices.GetRequiredService<IOptions<DemoOptions>>().Value;
        }

-->

</issue_description>

<agent_instructions>propose a PR for this issue, make it a draft, focus on correctness, we don't want to break anything</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes Wire up IServiceProvider when validating DataAnnotations attributes on Options #36009

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