Add EEP-59 Markdown highlighting for Erlang docs

[codeadict]

Adds Markdown injection support for EEP-59 -doc and -moduledoc attributes, including parenthesized forms.

Also recognizes erlang in fenced Markdown code blocks.

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[MrSubidubi]

Thanks for this as well!

Curious though, do other editors also handle the highlighting like this? While I do see how that could improve things, I also feel this could lead to confusion, as e.g. the nested highlighting looks a bit off.

[codeadict]

Thanks for this as well!

Curious though, do other editors also handle the highlighting like this? While I do see how that could improve things, I also feel this could lead to confusion, as e.g. the nested highlighting looks a bit off.

@MrSubidubi - I'm not sure about other editors but in Zed elixir does the same at https://github.com/zed-extensions/elixir/blob/main/languages/elixir/injections.scm and I work with it daily with no issues, maybe I can add a setting to have this on / off if it becomes ugly for some people