Missing CORS headers

I just tried various 1.2.x version and none of them set any CORS headers, so even running on localhost is failing for me due to different ports.

I fixed that locally by editing `node_modules/@codeceptjs/ui/bin/codecept-ui.js` and change

```javascript
const io = require('socket.io')();
```

to

```javascript
const io = require('socket.io')({
cors: {
origin: "http://localhost:3333",
credentials: true,
methods: ["GET", "POST"],
transports: ['websocket', 'polling']
},
allowEIO3: true
});
```

A proper solution would require to make the origin configurable.

Start with node_modules/@codeceptjs/ui/bin/codecept-ui.js and inspect how the Socket.IO server is created and how the UI server is configured. Make the CORS origin configurable while preserving localhost support, then verify that the UI works across different local ports and that the expected CORS headers are present.

Written by the indexing model from the issue text.