improved error handling

wizard-client/wizard-client-libgdx/core/src/main/java/eu/jonahbauer/wizard/client/libgdx/Client.java

@@ -1,5 +1,6 @@
 package eu.jonahbauer.wizard.client.libgdx;
 
+import eu.jonahbauer.wizard.client.libgdx.screens.ErrorScreen;
 import eu.jonahbauer.wizard.client.libgdx.state.ClientState;
 import eu.jonahbauer.wizard.client.libgdx.state.Menu;
 import eu.jonahbauer.wizard.common.machine.TimeoutContext;
@@ -33,7 +34,10 @@ public class Client extends TimeoutContext<ClientState, Client> {
     @Override
     protected void handleError(Throwable t) {
         // TODO better error handling
-        log.error("", t);
+        log.error("An error occurred.", t);
+
+        game.setScreen(new ErrorScreen(game, t.getMessage()));
+        error = true;
 
         var menu = new Menu();
         forceTransition(menu);