finish up rando config ui, remove randomizerEnabled CVar, fix seed strings not saving to config

i would like to have someone more aquainted with the UI system to look over the config menu at some point, as i do think it could be better.

src/dusk/settings.cpp

@@ -124,7 +124,6 @@ UserSettings g_userSettings = {
         .liveSplitEnabled {"game.liveSplitEnabled", false},
         .showSpeedrunRTATimer {"game.showSpeedrunRTATimer", true},
         .recordingMode {"game.recordingMode", false},
-        .randomizerEnabled {"game.randomizerEnabled", false},
         .showInputViewer {"game.showInputViewer", false},
         .showInputViewerGyro {"game.showInputViewerGyro", false}
     },
@@ -278,8 +277,6 @@ void registerSettings() {
     Register(g_userSettings.game.debugFlyCamLockEvents);
     Register(g_userSettings.game.allowBackgroundInput);
 
-    Register(g_userSettings.game.randomizerEnabled);
-
     Register(g_userSettings.backend.isoPath);
     Register(g_userSettings.backend.isoVerification);
     Register(g_userSettings.backend.graphicsBackend);