This needs to be added to SemanticTokensEncoder companion object (as it doesn't depend on negotiated legend), and should operate directly on two Vector[uinteger]
do you have in mind a real delta or a "fast" one? A fast one being "find common prefix and suffix of two vectors and don't resend those." A fast delta is utilized by rust-analyzer (and now by ocaml-lsp too)
See https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#textDocument_semanticTokens
This needs to be added to
SemanticTokensEncoder
companion object (as it doesn't depend on negotiated legend), and should operate directly on twoVector[uinteger]