fix(events): use the WebSocket global and drop the ws dependency

[georgeglarson]

• A human has tested these changes.

HUMAN:

Human verified, screenshot below.

Why

Both WebSocket clients picked their implementation like this:

if (typeof window !== 'undefined' && window.WebSocket) {
  WebSocketImpl = window.WebSocket;
} else {
  const ws = require('ws');   // ReferenceError in ESM
}

window is undefined in Node on every version, so Node always took the second branch, and require does not exist in an ESM module. The fallback never worked in the environment it was written for. It only appeared to work under the CommonJS Jest runner, which is why the existing tests had to fake the failure with jest.doMock('ws', ...).

Meanwhile WebSocket has been a global in Node since 22.4, and the CI floor is above that. So the fallback is dead code guarding a case that cannot happen.

Summary

• Both clients read globalThis.WebSocket. Browsers and Node both provide it.
• ws comes out of dependencies, so it stops shipping to consumers.
• package-import.test.ts deletes the global instead of mocking a module, which is the condition a consumer would actually hit rather than a simulation of it. Two tests added for the present-global path.

The load-time invariant is unchanged: reading a missing global yields undefined rather than throwing, and "no WebSocket implementation" still surfaces through onError at start().

Issue Number

No issue filed. Follows the Node 24 discussion in #proj-agent-canvas on 2026-08-29.

How to Test

npm ci && npm run lint && npm run build && npm run format:check && npm test

18 suites, 311 tests, 0 lint errors on Node 24.20.

The suite runs under CommonJS Jest, which is the reason the old bug hid, so it cannot prove the ESM path on its own. npm pack the branch, install the tarball into a project with "type": "module", and import the barrel:

import { RemoteWorkspace, WebSocketCallbackClient } from "@openhands/typescript-client";
new RemoteWorkspace({ host: "https://agent.example.com", workingDir: "/workspace", apiKey: "k" });
const c = new WebSocketCallbackClient({ host: "http://example.com", conversationId: "c1", callback: () => {}, onError: (e) => console.log("onError:", e.message) });
c.start(); c.stop();

On main that file throws before the first line runs. On this branch the barrel imports, the workspace constructs, and the client opens through globalThis.WebSocket.

Video/Screenshots

Type

• Bug fix
• Feature
• Refactor
• Breaking change
• Docs / chore

Notes

This subsumes #362. That PR changes the same window check to globalThis, which is the first half of this one. Close #362 in favour of this, or land it first and this rebases to just the deletion and the dependency drop. Whichever you prefer.

Independent of #368 and #369. The global exists on 22.12 as well as 24, so this does not depend on the floor moving.

[all-hands-bot]

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