Feature: Isolated decorator nodes.

I moved from prosemirror and thought the concept of isolating nodes would be useful.

For example I have a video decorator node, and it would be nice this node won't be deleted by backspace. Because the video might be playing while I am editing.

Or is it possible we achieve this thru some plugins?

The original prosemirror isolating definition.
[isolating](https://prosemirror.net/docs/ref/#model.NodeSpec.isolating)⁠?: [boolean](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Boolean)
When enabled (default is false), the sides of nodes of this type count as boundaries that regular editing operations, like backspacing or lifting, won't cross. An example of a node that should probably have this enabled is a table cell.