I think the only real way you can run make a language server understand comptime code is using the compiler as a library, similar to how Nim does it - nimsuggest (the tool for autocompletion, definitions, etc) is basically the compiler itself with some nimsuggest-specific stuff, so it understand macros, templates, compile time code evaluation, etc.

from what i understood, that is what they are planning to do, have an official built in language server