Math support

### Your use case

#### What would you like to do?

Write math like `$\sqrt{\delta}$` to print $\sqrt{\delta}$.

#### Why would you like to do it?

Cause math is less cool when reading LaTeX code.

#### How would you like to achieve it?

Just parse the code that starts and ends with a dollar, and then use something like MathJax to print it. This has already been implemented in Element Android and in element web (experimental).

### Have you considered any alternatives?

_No response_

### Additional context

_No response_

### Are you willing to provide a PR?

No