Issue Description:

Currently, DroolsLspServer creates its own instance of DroolsLspDocumentService;

    public DroolsLspServer() {
        textService = new DroolsLspDocumentService(this);
        workspaceService = new DroolsLspWorkspaceService();
    }

At the same time, DroolsLspDocumentService accept DroolsLspServer as parameter in constructor because it needs to retrieve the "client" from it

server.getClient()....

This could be improved a lot IMO; since the "client" is needed for the code to run, and this client is set inside DroolsLspServer:

    @Override
    public void connect(LanguageClient client) {
        this.client = client;
    }

The instantiation of DroolsLspDocumentService could happen here (or - its "initialization", i.e. setting the client directly in DroolsLspDocumentService), avoiding this reciprocal binding DroolsLspServer <-> DroolsLspDocumentService (that, generally speaking, is bad)

Acceptance Criteria:

Refactor to solve the reciprocal binding.