✨ 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/playback/worklet/index.ts

@@ -0,0 +1,58 @@
+// TODO add support for @/ to avoid relative imports
+import { Ring } from "../../common/ring"
+import * as Message from "./message"
+
+class Renderer extends AudioWorkletProcessor {
+	ring?: Ring
+	base: number
+
+	constructor() {
+		// The super constructor call is required.
+		super()
+
+		this.base = 0
+		this.port.onmessage = this.onMessage.bind(this)
+	}
+
+	onMessage(e: MessageEvent) {
+		const msg = e.data as Message.From
+		if (msg.config) {
+			this.onConfig(msg.config)
+		}
+	}
+
+	onConfig(config: Message.Config) {
+		this.ring = new Ring(config.ring)
+	}
+
+	// Inputs and outputs in groups of 128 samples.
+	process(inputs: Float32Array[][], outputs: Float32Array[][], _parameters: Record<string, Float32Array>): boolean {
+		if (!this.ring) {
+			// Paused
+			return true
+		}
+
+		if (inputs.length != 1 && outputs.length != 1) {
+			throw new Error("only a single track is supported")
+		}
+
+		if (this.ring.size() == this.ring.capacity) {
+			// This is a hack to clear any latency in the ring buffer.
+			// The proper solution is to play back slightly faster?
+			console.warn("resyncing ring buffer")
+			this.ring.clear()
+			return true
+		}
+
+		const output = outputs[0]
+
+		const size = this.ring.read(output)
+		if (size < output.length) {
+			// TODO trigger rebuffering event
+		}
+
+		return true
+	}
+}
+
+registerProcessor("renderer", Renderer)