feat(HTTP.SYS): on-demand TLS client hello retrieval

[DeagleGross]

HTTP.SYS only on-demand TLS client hello

As discussed in api proposal we are doing 2 things here:

1. removing previous "callback" API HttpSysOptions.TlsClientHelloBytesCallback
2. implementing an on-demand request of TlsClientHello via win API. It is done by exposing a method on a new feature interface IHttpSysRequestPropertiesFeature: IHttpSysRequestPropertiesFeature.TryGetTlsClientHello.

TlsFeaturesObserve.Program sample shows the usage of that feature and this API in particular:

app.Use(async (context, next) =>
{
    var connectionFeature = context.Features.GetRequiredFeature<IHttpConnectionFeature>();
    var httpSysPropFeature = context.Features.GetRequiredFeature<IHttpSysRequestPropertyFeature>();

    // first time invocation to find out required size
    var success = httpSysPropFeature.TryGetTlsClientHello(Array.Empty<byte>(), out var bytesReturned);
    Debug.Assert(!success);
    Debug.Assert(bytesReturned > 0);

    // rent with enough memory span and invoke
    var bytes = ArrayPool<byte>.Shared.Rent(bytesReturned);
    success = httpSysPropFeature.TryGetTlsClientHello(bytes, out _);
    Debug.Assert(success);

    await context.Response.WriteAsync($"[Response] connectionId={connectionFeature.ConnectionId}; tlsClientHello.length={bytesReturned}; tlsclienthello start={string.Join(' ', bytes.AsSpan(0, 30).ToArray())}");
    await next(context);
});

Implements #61625

[BrennanConroy]

@tdykstra for docs pass?

[tdykstra]

Just A few nits.

[tdykstra]

Avoid future tense per the style guide.

Suggested change

	/// <param name="tlsClientHelloBytesDestination">Where the raw bytes of the TLS Client Hello message will be written.</param>
	/// <param name="tlsClientHelloBytesDestination">Where the raw bytes of the TLS Client Hello message are written.</param>

[tdykstra]

Suggested change

	// if buffer supplied is too small, `bytesReturned` will have proper size
	// if buffer supplied is too small, `bytesReturned` has proper size

[tdykstra]

Suggested change

	/// If non-successful for other reason throws an exception.
	/// If unsuccessful for other reason throws an exception.