DocumentSyncMode
How a document's changes should be synchronized to the server, as negotiated through the server's textDocumentSync capability.
Mirrors the semantics upstream @codemirror/lsp-client derives from the same capability: whether open/close notifications are sent, and whether content is synced incrementally, in full, or not at all.
Parameters
openClose
Whether textDocument/didOpen and textDocument/didClose notifications should be sent.
change
How content changes are synced (TextDocumentSyncKind.NONE, TextDocumentSyncKind.FULL, or TextDocumentSyncKind.INCREMENTAL).