Allow focusing a newly-created inline content after insertion

[ClementEXWiki]

Is your feature request related to a problem? Please describe.
I have some custom inline contents that are basic wrappers around their content (e.g. subscript / superscript). This means that, when inserted, they are basically invisible until they are actually filled with a content.

Describe the solution you'd like
Allow focusing the inline content's inner WYSIWYG area after insertion.

Describe alternatives you've considered
Currently I'm inserting the element with a default text, which is not ideal for two reasons:

1. The default text needs to be removed by the user
2. The cursor gets pushed right to the inserted inline content, requiring the user to go back to the left to edit it

Additional context
N/A

[nperez0111]

@ClementEXWiki, why should subscript & superscript act any differently than something like underline or bold? Should they be inline content, or should they be styles?

[ClementEXWiki]

I'm currently using inline contents to circumvent the fact subscript and superscript are not available natively in BlockNote right now, and given our code structure it's easier to do that than adding custom styles.

Long-term, subscript and subscript would be better as native styles, yes.

Also this was just a single example, we're going to get lots of actual custom inline contents, that may be empty when inserted, and it would be nice to have a way to put the cursor inside the inline content after insertion.