Bookmarks comment

### Description

Hi, I hope the title is clear.
It would be very helpful if each bookmark had the option to add a comment with longer formated text about what the bookmark is about. The inserted comment could then be displayed after hovering over the bookmark icon in the source code.

M

### Use case/motivation

_No response_

### Related issues

_No response_

### Are you willing to submit a pull request?

No

The issue names no files, tests, or entry points. Start by locating NetBeans' bookmark implementation and the editor UI that displays bookmark icons, then trace how bookmark data is stored and surfaced on hover. Done means bookmarks can hold formatted comments and display them when hovering over the corresponding icon.

Written by the indexing model from the issue text.