[nostalgia/studio] Cleanup save hooks and add unsaved changes marker to tabs

src/nostalgia/studio/lib/editor.cpp

@@ -13,15 +13,12 @@ namespace nostalgia::studio {
 Editor::Editor(QWidget *parent): QWidget(parent) {
 }
 
-void Editor::saveItem() {
-}
-
 QUndoStack *Editor::undoStack() {
 	return nullptr;
 }
 
 void Editor::save() {
-    save();
+    saveItem();
     setUnsavedChanges(false);
 }
 
@@ -30,4 +27,7 @@ void Editor::setUnsavedChanges(bool uc) {
     emit unsavedChangesUpdate(uc);
 }
 
+void Editor::saveItem() {
+}
+
 }