Add new Streams API module to v0.51 release notes

release notes/v0.51.0.md

@@ -15,9 +15,66 @@ k6 `v0.51.0` is here 🎉! This release includes:
 
 _optional intro here_
 
-### `<big_feature_1>` `#pr`
+### Introduction of `k6/experimental/streams` module #3696
+
+This release of k6 introduces the new `k6/experimental/streams` module, which partially supports the JavaScript
+Streams API, focusing initially on the `ReadableStream` construct.
+
+With the `ReadableStream`, users can define and consume data streams within k6 scripts. This is particularly useful for
+efficiently handling large datasets or for processing data sequentially in a controlled flow.
+
+#### Limitations
+
+This initial implementation is an experimental feature and does not include support for the whole Streams API feature set. 
+
+Currently, users can define and consume readable streams . However, this release does not include support for byte readers
+and controllers, nor does it include support the `tee`, `pipeTo`, and
+`pipeThrough` methods of the `ReadableStream` object.
+
+#### Example: streaming numbers 
+
+The following example demonstrates creating and consuming a simple stream that emits numbers until it reaches a predfined
+limit:
+
+```javascript
+import { ReadableStream } from 'k6/experimental/streams'
+import { setTimeout } from 'k6/timers'
+
+function numbersStream() {
+    let currentNumber = 0
+
+	return new ReadableStream({
+		start(controller) {
+			const fn = () => {
+				if (currentNumber < 5) {
+					controller.enqueue(++currentNumber)
+					setTimeout(fn, 1000)
+					return;
+				}
+
+				controller.close()
+			}
+			setTimeout(fn, 1000)
+		},
+	})
+}
+
+export default async function () {
+	const stream = numbersStream()
+	const reader = stream.getReader()
+
+	while (true) {
+		const { done, value } = await reader.read()
+		if (done) break
+		console.log(`received number ${value} from stream`)
+	}
+
+	console.log('we are done')
+}
+```
+
+For more advanced examples, please head to the MDN Web Docs on the [Streams API](https://developer.mozilla.org/en-US/docs/Web/API/Streams_API).
 
-_what, why, and what this means for the user_
 
 ### `<big_feature_n>` `#pr`