Add markmap supported

[llhhbc]

Add markmap supported for write mindmap with markdown.

You can know markmap by https://markmap.js.org/repl and https://github.com/gera2ld/markmap/tree/master/packages/markmap-autoloader

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[llhhbc]

#610

[LisaFC]

This is great! Can you add some brief documentation in https://www.docsy.dev/docs/adding-content/lookandfeel/ with all the other map/chart/diagram features? Doesn't need to be perfect, I can do an editorial review.

[llhhbc]

This is great! Can you add some brief documentation in https://www.docsy.dev/docs/adding-content/lookandfeel/ with all the other map/chart/diagram features? Doesn't need to be perfect, I can do an editorial review.

Pull a merge request to this docs's project? I will try.

[LisaFC]

This is great! Can you add some brief documentation in https://www.docsy.dev/docs/adding-content/lookandfeel/ with all the other map/chart/diagram features? Doesn't need to be perfect, I can do an editorial review.

Pull a merge request to this docs's project? I will try.

Yes thanks! I'll happily do any editing required. :)

[llhhbc]

This is great! Can you add some brief documentation in https://www.docsy.dev/docs/adding-content/lookandfeel/ with all the other map/chart/diagram features? Doesn't need to be perfect, I can do an editorial review.

Pull a merge request to this docs's project? I will try.

Yes thanks! I'll happily do any editing required. :)

@LisaFC
Sorry for the delay, I have already added the relevant document description

[LisaFC]

Thanks! Sorry for the late review, I was on vacation. Will take a look now!

[LisaFC]

This looks great! Thanks for adding the feature!