fix: errors caused by events fired while editor is not initialized yet

[neSpecc]

Problem

Users reported problems with errors that happen by document click at the moment when Editor is not fully initialised:

Cause

Our current TS setup is not strict. So we missed some cases, when module nodes field can contain undefined values (when UI is not fully constructed)

Se we don't have check for undefined in many places, including documentClicked or document.onMouseOver event handlers.

Solution

• Add undefined type to some module nodes
• Handle undefined case in event handlers
• Wrap document event binding with reequestIdleCallback to bind them only when UI is ready.