Add setting for UI scale (#2326)

src/dusk/ui/settings.cpp

@@ -770,6 +770,12 @@ SettingsWindow::SettingsWindow(bool prelaunch) : mPrelaunch(prelaunch) {
                     },
                 .isDisabled = [] { return IsMobile; },
             });
+
+        config_int_select(leftPane, rightPane, getSettings().video.uiScale,
+            "UI Scale", 
+            "Scales the Dusklight interface relative to the display's DPI scale. Has no effect on the game's UI and HUD.",
+            50, 200, 25, {}, {}, "%");
+
         leftPane.add_section("Resolution");
         graphics_tuner_control(*this, leftPane, rightPane,
             getSettings().game.internalResolutionScale,