[clang] [clang-tools-extra] [clangd] Support #embed highlighting in clangd (PR #212036)

[Nathan Ridge via cfe-commits]

https://github.com/HighCommander4 requested changes to this pull request.

Clangd does not send semantic tokens for any other preprocessor directives (`#define`, `#ifdef`, `#include`...), leaving those to client-side highlighting. I think it shouldn't be sending semantic tokens for `#embed` either.

https://github.com/llvm/llvm-project/pull/212036