Checklist

• I have searched the issue tracker for open issues that relate to the same feature, before opening a new one.
• This issue only relates to a single feature. I will open new issues for any other features.

Is your feature request related to a problem?

The official documentation suggests using the handle token internally with library name + random number to subscribe to a signal before it happens and the read the result after the portal invocation to avoid a race. We are not doing so.

Describe the solution you'd like to see.

Remove HandleToken fields from the options API and use it internally to subscribe to events before they happen.