✨ Bookmark Navigator

### Description

Introduce a Bookmark Navigator panel that allows users to view, organize, and quickly jump to bookmarked lines across files. This would streamline navigation in large codebases and improve productivity when working across multiple sections of a project.

### Proposed Features

- List all bookmarks in the current workspace/project
- Show file name, line number, and a preview of the bookmarked line
- Allow bookmarks to be renamed or annotated with custom labels
- Clicking a bookmark scrolls the editor to the corresponding line
- Ability to group or filter bookmarks by file, folder, or tag
- Keyboard shortcuts for toggling the navigator and adding/removing bookmarks
- Option to persist bookmarks across sessions

### Additional Context:

This would be especially useful for users who frequently jump between key parts of their code or need to track multiple areas while debugging or implementing features.

The issue names no files, tests, or entry points; first survey the existing bookmark and editor navigation implementation in the CodeEdit macOS app. Define acceptance checks for listing, jumping to, organizing, labeling, filtering, keyboard control, and persistence before implementation.

Written by the indexing model from the issue text.