V2 suggestions / diff: changing attrs (e.g.: heading level) does not show

[YousefED]

Describe the bug
Changing a node attr such as a heading level does not show in diff / suggestion mode

To Reproduce
Steps to reproduce the behavior:

1. Go to https://y-prosemirror-demo.netlify.app/
2. Type "Hello world", set to heading
3. Set suggestions to "Edit"
4. Select text, change to heading level 2

Notice how the change is visible (the heading level changes), but not shown as a suggested-change

Expected behavior
I expect to be able to type in the original content, similar to how this works in Google Docs.

Screenshots

Additional context

• I'm a sponsor 💖
• This issue is a blocker for my project.