Fix cyclic interaction error message issues

The message was duplicating on unfixed sorts, and it wasn't being
displayed in an error message dialog.

src/backend/plugin_sorter.cpp

@@ -101,6 +101,10 @@ namespace loot {
         indexMap.clear();
         oldLoadOrder.clear();
 
+        // Clear any existing game-specific messages, as these only relate to
+        // state that has been changed by sorting.
+        game.ClearMessages();
+
         progressCallback(boost::locale::translate("Building plugin graph..."));
         BuildPluginGraph(game, language);
 
@@ -153,9 +157,6 @@ namespace loot {
             plugins.push_back(graph[vertex]);
         }
 
-        // Clear any existing game-specific messages, as these only relate to
-        // state that has been changed by sorting.
-        game.ClearMessages();
         game.SetLoadOrderSorted(true);
 
         return plugins;

src/gui/html/js/events.js

@@ -102,8 +102,10 @@ function onSortPlugins() {
     loot.game.globalMessages = result.globalMessages;
 
     if (!result.plugins) {
-      loot.Dialog.closeProgress();
-      return;
+      const message = result.globalMessages.find((item) => {
+        return item.content[0].str.startsWith('Cyclic interaction detected');
+      });
+      throw new Error(loot.l10n.translate('Failed to sort plugins. Details: ' + message.content[0].str));
     }
 
     /* Check if sorted load order differs from current load order. */