fix: parse initializationOptions even more correctly

But because of some problem within the V's json decode generator it's
not possible to handle it prefectly with V's json module yet (optional
type not handled correctly for sumtype & other types except struct)

src/lsp/initialize.v

@@ -1,5 +1,13 @@
 module lsp
 
+// TODO: These LSPAny need to change to `?LSPAny` too.
+type LSPAny = []LSPAny
+    | map[string]LSPAny
+	| f64
+	| bool
+	| string
+
+
 // method: ‘initialize’
 // response: InitializeResult
 pub struct InitializeParams {
@@ -8,7 +16,8 @@ pub mut:
 	client_info            ClientInfo  @[json: clientInfo]
 	root_uri               DocumentUri @[json: rootUri]
 	root_path              DocumentUri @[json: rootPath]
-	initialization_options string      @[json: initializationOptions; skip]
+	// TODO: Change this to `?LSPAny` once V fixed its JSON decoder codegen. (or shall we use json2?)
+	initialization_options LSPAny      @[json: initializationOptions]
 	capabilities           ClientCapabilities
 	trace                  string
 	workspace_folders      []WorkspaceFolder @[skip]

src/server/general.v

@@ -25,7 +25,10 @@ pub fn (mut ls LanguageServer) initialize(params lsp.InitializeParams, mut wr Re
 	ls.status = .initialized
 
 	ls.progress.support_work_done_progress = params.capabilities.window.work_done_progress
-	ls.initialization_options = params.initialization_options.fields()
+	options := params.initialization_options
+	if options is string {
+		ls.initialization_options = options.fields()
+	}
 
 	ls.print_info(params.process_id, params.client_info)
 	ls.setup()