Syntax highlighting for typc and typm

[uben0]

In raw blocks in Typst and other markup languages like Markdown, the typc and typm syntax indications, correspond to Typst's code and Typst's math. Currently, the Tree-Sitter syntax only recognizes typ and typst.

```typ
= Hello
#v(1em)
World
```

```typc
v(1em)
```

```typm
x^2 = y
```