refactor: adapt rest of the codebase to the new resource model

In order to access the ModFolderModel from the ModFolderPage, i created
a new m_model for the correct type, shadowing the m_model of type
ResourceFolderModel. This creates two shared_ptr references to the same object,
but since they will have the same lifetime, it doesn't generate a memory
leak.

Signed-off-by: flow <flowlnlnln@gmail.com>

launcher/minecraft/mod/ResourcePackFolderModel.cpp

@@ -35,5 +35,4 @@
 
 #include "ResourcePackFolderModel.h"
 
-ResourcePackFolderModel::ResourcePackFolderModel(const QString &dir) : ResourceFolderModel(dir) {
-}
+ResourcePackFolderModel::ResourcePackFolderModel(const QString &dir) : ResourceFolderModel(QDir(dir)) {}