Add failing cloudflare integration suite

This is currently failing but acts as a starting point for verifying that
we can run the Replicate library on Cloudflare workers.

The test creates a cloudflare worker that uses the streaming API (as this
exercises a bunch of the API surface area) and uses the experimental
unstable_dev library to run the worker in a test. We then verify that
the test receives a successful response.

Currently we have the following issues:

* `node:crypto` needs to be replaced with web crypto (node >= 15).
* replace Buffer with Blob where possible or abstract behind a conditional.
* `process.env` also needs to be accessed behind a conditional.

Author: aron

integration/cloudflare-worker/.gitignore

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+.wrangler
+node_modules

integration/cloudflare-worker/index.js

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+import Replicate from "replicate";
+
+const replicate = new Replicate();
+
+export default {
+  async fetch(_request, _env, _ctx) {
+    const stream = new ReadableStream({
+      async start(controller) {
+        for await (const event of replicate.stream(
+          "replicate/hello-world:5c7d5dc6dd8bf75c1acaa8565735e7986bc5b66206b55cca93cb72c9bf15ccaa",
+          {
+            input: {
+              text: "Colin CloudFlare",
+            },
+          }
+        )) {
+          controller.enqueue(`${event}`);
+        }
+        controller.close();
+      },
+    });
+
+    return new Response(stream);
+  },
+};

integration/cloudflare-worker/index.test.js

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+// https://developers.cloudflare.com/workers/wrangler/api/#unstable_dev
+import { unstable_dev as dev } from "wrangler";
+import { test, after, before } from "node:test";
+import assert from "node:assert";
+
+let worker;
+
+before(async () => {
+  worker = await dev("index.js", {
+    experimental: { disableExperimentalWarning: true },
+  });
+});
+
+after(async () => {
+  if (!worker) {
+    // If no worker the before hook failed to run and the process will hang.
+    process.exit(1);
+  }
+  await worker.stop();
+});
+
+test("worker streams back a response", { timeout: 1000 }, async (t) => {
+  const resp = await worker.fetch("/", { signal: t.signal });
+  const text = await resp.text();
+
+  assert.equal(resp.ok, true, "status is 2xx");
+  assert(text.length > 0, "body.length is greater than 0");
+});