feat: publish shared task and reply activities through MCP

src/features/activities/http-events.server.test.ts

@@ -0,0 +1,54 @@
+// @vitest-environment node
+import { afterEach, assert, expect, it, vi } from "vitest";
+import { activityEvents } from "./http-events.server";
+
+afterEach(() => vi.useRealTimers());
+
+it("invalidates on connection and publication, and unsubscribes on disconnect", async () => {
+  let notify = () => {};
+  const unsubscribe = vi.fn<() => void>();
+  const abort = new AbortController();
+  const response = activityEvents(
+    new Request("http://workspace.invalid/api/activities/events", { signal: abort.signal }),
+    (listener) => {
+      notify = listener;
+      return unsubscribe;
+    },
+    () => true,
+  );
+  assert.isNotNull(response.body);
+  const reader = response.body.getReader();
+  const initial = await reader.read();
+  expect(new TextDecoder().decode(initial.value)).toBe("event: change\ndata: {}\n\n");
+  notify();
+  expect(new TextDecoder().decode((await reader.read()).value)).toBe("event: change\ndata: {}\n\n");
+  abort.abort();
+  expect((await reader.read()).done).toBe(true);
+  expect(unsubscribe).toHaveBeenCalledOnce();
+});
+
+it("refuses an unauthorized subscriber", () => {
+  const subscribe = vi.fn<(listener: () => void) => () => void>();
+  expect(
+    activityEvents(new Request("http://workspace.invalid/events"), subscribe, () => false).status,
+  ).toBe(401);
+  expect(subscribe).not.toHaveBeenCalled();
+});
+
+it("closes an expired browser session during keepalive", async () => {
+  vi.useFakeTimers();
+  let authorized = true;
+  const unsubscribe = vi.fn<() => void>();
+  const response = activityEvents(
+    new Request("http://workspace.invalid/events"),
+    () => unsubscribe,
+    () => authorized,
+  );
+  assert.isNotNull(response.body);
+  const reader = response.body.getReader();
+  await reader.read();
+  authorized = false;
+  await vi.advanceTimersByTimeAsync(15_000);
+  expect((await reader.read()).done).toBe(true);
+  expect(unsubscribe).toHaveBeenCalledOnce();
+});