fix: hardcore mode UI not locking difficulty/gamemode on world load

Three issues fixed:

- Save file path used hardcoded saveData.ms but new 4JLibs names files
  as <title>.ms. ReadLevelNameFromSaveFile now constructs the correct
  path with fallback to saveData.ms for old saves.
- The level.dat code path for reading the hardcore flag (sidecar rename)
  returned early without ever parsing level.dat. Now stores the sidecar
  name and continues to read the hardcore flag from NBT.
- The thumbnail host options path could overwrite m_bHardcore to false.
  Now only upgrades to true, never downgrades.
- Load menu constructor and tick handler both lock difficulty slider to
  Hardcore and gamemode to Survival when hardcore is detected.
- Hide title logo on load menu to match create world menu.

Minecraft.Client/Common/UI/UIScene_LoadMenu.cpp

@@ -281,6 +281,11 @@ UIScene_LoadMenu::UIScene_LoadMenu(int iPad, void *initData, UILayer *parentLaye
 				WCHAR TempString[256];
 				swprintf((WCHAR *)TempString, 256, L"%ls: %ls", app.GetString(IDS_SLIDER_DIFFICULTY), L"Hardcore");
 				m_sliderDifficulty.init(TempString, eControl_Difficulty, 0, 4, 4);
+
+				// Hardcore locks game mode to Survival
+				m_iGameModeId = GameType::SURVIVAL->getId();
+				m_bGameModeCreative = false;
+				m_buttonGamemode.setLabel(app.GetString(IDS_GAMEMODE_SURVIVAL));
 			}
 		}
 #endif
@@ -421,15 +426,7 @@ void UIScene_LoadMenu::updateTooltips()
 void UIScene_LoadMenu::updateComponents()
 {
 	m_parentLayer->showComponent(m_iPad,eUIComponent_Panorama,true);
-
-	if(RenderManager.IsWidescreen())
-	{
-		m_parentLayer->showComponent(m_iPad,eUIComponent_Logo,true);
-	}
-	else
-	{
-		m_parentLayer->showComponent(m_iPad,eUIComponent_Logo,false);
-	}
+	m_parentLayer->showComponent(m_iPad,eUIComponent_Logo,false);
 }
 
 wstring UIScene_LoadMenu::getMoviePath()
@@ -573,7 +570,9 @@ void UIScene_LoadMenu::tick()
 				m_MoreOptionsParams.bAllowFriendsOfFriends = TRUE;
 			}
 
-			m_bHardcore = app.GetGameHostOption(uiHostOptions, eGameHostOption_Hardcore) > 0;
+			// Use thumbnail host options if available, otherwise preserve the level.dat value
+			if (app.GetGameHostOption(uiHostOptions, eGameHostOption_Hardcore) > 0)
+				m_bHardcore = true;
 			if (m_bHardcore)
 			{
 				WCHAR TempString[256];