feat(jui): (re-)add transitional screens

Adds a new MessageScreen class to display custom messages and restores areas where ReceivingLevelScreen was used

Minecraft.Client/UI/Screens/MessageScreen.cpp

@@ -0,0 +1,19 @@
+#include "../../Platform/stdafx.h"
+#include "MessageScreen.h"
+
+MessageScreen::MessageScreen(const std::wstring& message) {
+    this->message = message;
+}
+
+void MessageScreen::keyPressed(char eventCharacter, int eventKey) {}
+
+void MessageScreen::init() { buttons.clear(); }
+
+void MessageScreen::buttonClicked(Button* button) {}
+
+void MessageScreen::render(int xm, int ym, float a) {
+    renderDirtBackground(0);
+    drawCenteredString(font, message, width / 2, height / 2 - 50, 0xffffff);
+
+    Screen::render(xm, ym, a);
+}