[Feature] mind map block

[XJY00]

You can use block notes to create a simple mind map + outline note,
and implement it using a mode-switching button or an interface.
In outline mode, each line of content and its indentation level serve as mind map nodes.
It looks like an unordered list in Markdown syntax, with indentation controlling the hierarchical levels.
The rendering style of the mind map can be displayed as an embedded block within the editor.
Additionally, there is an independent whiteboard page for rendering (provided for sidebar use cases that do not require WYSIWYG).
The mind map only needs to support node collapsing and expanding, keeping the rendering style simple.
For complete mind map rendering requirements, you can integrate with the simplemindmap project.
Vditor

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