WIP: Add LethalConfig with suitable custom options

Draft because needs testing in multiplayer environment. Apparently,
both isClinet and isHost are true in single player.

FIXME:
If LethalConfig panel opened while orbiting, and then the round has started, it would still
be possible to modify the values at least once. This is presumably a bug in LethalConfig,
because it doesn't check the callback again before actually applying the change.

MuzikaGromche/Plugin.cs

@@ -307,7 +307,7 @@ namespace MuzikaGromche
                 var slider = new IntSliderConfigItem(track.Weight.Entry, new IntSliderOptions
                 {
                     RequiresRestart = false,
-                    CanModifyCallback = CanModifyWeightsNow,
+                    CanModifyCallback = CanModifyCallback,
                 });
                 LethalConfigManager.AddConfigItem(slider);
             }
@@ -323,7 +323,7 @@ namespace MuzikaGromche
             ConfigManager.Register(this);
         }
 
-        public static CanModifyResult CanModifyWeightsNow()
+        public static CanModifyResult CanModifyCallback()
         {
             var startOfRound = StartOfRound.Instance;
             if (!startOfRound)