WebSocket clients ignore Node's global WebSocket in ESM builds

[georgeglarson]

Description

The package is emitted as ESM, and Node 22 provides a standards-compatible globalThis.WebSocket. The conversation and bash event clients only check window.WebSocket, then attempt require('ws'). Since require is unavailable in ESM, starting either client reports that no WebSocket implementation is available.

Steps to reproduce

1. Install dependencies and build the package on Node 22.
2. Import WebSocketCallbackClient from dist/events/websocket-client.js in an ESM process.
3. Create a client and call start().

node --input-type=module -e "const {WebSocketCallbackClient}=await import('./dist/events/websocket-client.js'); const client=new WebSocketCallbackClient({host:'http://127.0.0.1:9',conversationId:'test',callback:()=>{},onError:console.error}); client.start(); client.stop()"

Expected behavior

The client uses Node's global WebSocket constructor.

Actual behavior

The error callback receives WebSocket implementation not available, even though globalThis.WebSocket exists. This is reproducible after the repository setup command uv sync --dev and the TypeScript package build complete.

Acceptance Criteria

• The TypeScript WebSocket callback clients use globalThis.WebSocket in Node ESM when available.
• The fallback path still supports injected WebSocket implementations and browser window.WebSocket.
• A TypeScript client test covers Node's global WebSocket constructor path.

Environment

• Node.js 22.22.2
• Current main

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[georgeglarson]

Superseded by the bug-form issue #4846, which carries the repository's required issue metadata for PR readiness.