[Feature]: Introduction of Reactive Streams

[eneshoxha]

Describe the solution you'd like
In the Cortex Data Framework, we are introducing Reactive support for our IStream implementations.

Below is an example of how Stream can look.

var counter = new Stream<int>(0);
var doubled = counter.Map(x => x * 2);

using var _ = doubled.Subscribe(x => Console.WriteLine($"doubled: {x}"));

counter.Emit(1); // prints 2
counter.Emit(2); // prints 4

// Destiny binding: keep target wired to source forever (until disposed)
var uiLabel = new Stream<string>();
using var bind = counter.Destiny(uiLabel, v => $"Count: {v}");

// anywhere in UI
uiLabel.Subscribe(text => label.Text = text);