✨ feat: Host a relay on Hetzner (#114)

We are hosting a [MoQ](https://quic.video) relay on a remote (bare
metal) server on Hetzner

With a lot of help from @victorpahuus

packages/moq/contribute/segment.ts

@@ -0,0 +1,45 @@
+import { Chunk } from "./chunk"
+
+export class Segment {
+	id: number
+
+	// Take in a stream of chunks
+	input: WritableStream<Chunk>
+
+	// Output a stream of bytes, which we fork for each new subscriber.
+	#cache: ReadableStream<Uint8Array>
+
+	timestamp = 0
+
+	constructor(id: number) {
+		this.id = id
+
+		// Set a max size for each segment, dropping the tail if it gets too long.
+		// We tee the reader, so this limit applies to the FASTEST reader.
+		const backpressure = new ByteLengthQueuingStrategy({ highWaterMark: 8_000_000 })
+
+		const transport = new TransformStream<Chunk, Uint8Array>(
+			{
+				transform: (chunk: Chunk, controller) => {
+					// Compute the max timestamp of the segment
+					this.timestamp = Math.max(chunk.timestamp + chunk.duration)
+
+					// Push the chunk to any listeners.
+					controller.enqueue(chunk.data)
+				},
+			},
+			undefined,
+			backpressure,
+		)
+
+		this.input = transport.writable
+		this.#cache = transport.readable
+	}
+
+	// Split the output reader into two parts.
+	chunks(): ReadableStream<Uint8Array> {
+		const [tee, cache] = this.#cache.tee()
+		this.#cache = cache
+		return tee
+	}
+}