instant saves as a toggle instead of default

src/dusk/settings.cpp

@@ -31,6 +31,7 @@ UserSettings g_userSettings = {
         .fastClimbing {"game.fastClimbing", false},
         .noMissClimbing {"game.noMissClimbing", false},
         .fastTears {"game.fastTears", false},
+        .instantSaves {"game.instantSaves", false},
 
         // Preferences
         .enableMirrorMode {"game.enableMirrorMode", false},
@@ -85,6 +86,7 @@ void registerSettings() {
     Register(g_userSettings.game.instantDeath);
     Register(g_userSettings.game.fastClimbing);
     Register(g_userSettings.game.fastTears);
+    Register(g_userSettings.game.instantSaves);
     Register(g_userSettings.game.enableMirrorMode);
     Register(g_userSettings.game.invertCameraXAxis);
     Register(g_userSettings.game.enableBloom);