Provide semantic tokens for document delta

[radeksimko]

Current Version

0.11.0

Use-cases

Currently the server only provides semantic tokens for a whole document. Documents are changed while the user is typing, which in turn means that tokens are requested frequently for any new version of the whole document, which can be suboptimal for larger documents.

A client can announce supports for deltas via relevant capability which effectively means it will maintain state of tokens for any given document itself and then only request deltas by providing the last resultId and then mutate the state based on received deltas.

Proposal

Support textDocument/semanticTokens/full/delta and opt into this feature via SemanticTokensOptions.