Is your feature request related to a problem? Please describe.
Not specifically.

Describe the solution you'd like
I would like to see my step runs show the correct syntax when I'm editing GH Actions or Workflows. Thank you!

Additional context

IntelliJ supports this via a feature called Language Injection. Users can either add a comment before the key such as # language=sh or modify their JSON Schema to provide the "x-intellij-language-injection": "Shell Script" property.

For VSCode, a request for generic support didn't gain much traction. Based on the discussion in microsoft/vscode#1751 it seems the preferred way to do this is with an extension using Grammar Injection or Embedded Languages.