Add other markdown syntax

[usecodelee]

trafficstars

This project is great！😄

But I don’t know how to add other markdown syntax. 😭

[cloverhearts]

Thank you for your report. I will consider additional guidance or structural changes.

[saiddjelmo]

That would be great! For example adding embed image ![text](https://example-image.jpg) or horizontal rule ....

[FOWind]

Support more markdown features is better.

The most important features I think are:

1. embed image support ![text](https://example-image.jpg)
2. link support [example](https://example.org)
3. table syntax support
4. embed flowchart syntax by mermaid
5. embed latex formula by Katex