Specify default math class in documentation

[MDLC01]

Description

On the General Symbols page, I would like the default math class (which can be overridden with math.class) to be indicated when clicking on a character.

Use Case

Knowing what the default math class of a character is easily.

[MDLC01]

Good news: this feature seems to have been implemented at https://staging.typst.app/docs/reference/symbols/sym/!

[laurmaedje]

Yeah, I think we can just close this. The docs changes will definitely go into the main version, so it's kind of like closing a bug in the dev compiler even though it's not released yet.