Support for camunda extension "Escape variable names"?

[makepanic]

Is your feature request related to a problem? Please describe

Hi,
thanks for maintaining this great grammar for feel.
I'm wondering if it should also support escaped variables via backticks as defined in the feel guides: https://docs.camunda.io/docs/components/modeler/feel/language-guide/feel-variables/#escape-variable-names

I know it's marked as camunda extension but should the tokenizer also detect these as VariableName?
Right now it just errors. This also happens in the camunda modeler.

Describe the solution you'd like

`first name`

`tracking-id`

order.`total price`

should output VariableName tokens without errors.

Describe alternatives you've considered

Fork this library and add support for the camunda extension which might not be intended to be included in the base grammar.

Additional context

[nikku]

Thanks for the issue. This repository is not the right place for such an extension. But we actively discuss a @camunda fork, allowing us to implement Camunda-specific quirks there.

[nikku]

What we could do, of course, is to implement this as a grammar dialect, i.e. camunda.