chatgui: postChatSetting в хедер, chat_core_get_inst include, chat→chatserver

tools/chatgui/src/invitedialog.cpp

@@ -6,6 +6,7 @@
 #include "../transport/gui_bridge.h"
 #include "../db/db_manager.h"
 extern "C" {
+#include "chat/chat_core.h"
 #include "chat/chat_sync.h"
 #include "transport_layer/secure_channel.h"
 }