fix(memory leak): IndexedPack too large to live inside a qlist without pointers ()

Signed-off-by: Rachel Powers <508861+Ryex@users.noreply.github.com>

launcher/modplatform/ModIndex.h

@@ -23,6 +23,7 @@
 #include <QString>
 #include <QVariant>
 #include <QVector>
+#include <memory>
 
 class QIODevice;
 
@@ -83,6 +84,8 @@ struct ExtraPackData {
 };
 
 struct IndexedPack {
+    using Ptr = std::shared_ptr<IndexedPack>;
+
     QVariant addonId;
     ResourceProvider provider;
     QString name;