support for embedded languages

[ceymard]

It would be great if the schemas could define values as being from a given language so that it gets syntax highlighted accordingly.

For instance, SQL database migrations specified in yaml files would gain a lot by having SQL colorized !
There is the yaml-embedded-languages, but it isn't aware of what the yaml file is about, it just colorizes based on a comment. I feel it would be cleaner if the schema provided this information. I am not sure of how this would be accomplished, however...

[rcjsuen]

Embedding languages is a non-trivial problem that requires support from the LSP client as well. See rcjsuen/dockerfile-language-server#273 for a similar request in a different language server.