MyST links to anchor links

Describe the bug

Anchor links don’t work.

[Signal](../api/signal) compiles in Sphinx but does not have an anchor link.

[Signal](../api/signal#torchsynth.signal.Signal) does not generate a link: “WARNING: ‘myst’ reference target not found: …/api/signal#torchsynth.signal.Signal”

```{eval-rst}
(:class:`~torchsynth.module.VCO`)`
```

works but creates a new paragraph

To Reproduce

Try to link to a particular anchor location in a particular file, e.g. above.

Expected behavior

There should be a way to link to MyST link to anchor locations OR an eval-rst that doesn’t create a new paragraph.

Environment

• Python Version [e.g. 3.7.1]: 3.8.5
• Package versions or output of jupyter-book --version: 0.13.5 + Sphinx
• Operating System: OSX

[chrisjsewell]

Good to hear 😄 The role syntax is detailed here: https://myst-parser.readthedocs.io/en/latest/using/syntax.html#roles-an-in-line-extension-point, but any feedback on improving this is welcome

(on a related note, I’m also finishing up https://github.com/executablebooks/rst-to-myst)

[turian]

Wow! @chrisjsewell thank you.