feat(RD): add texture pack downloader

This extends the resource pack downloader, with the custom behavior of
filtering the versions that shows up, to those <= 1.6. As always, Flame
is funky and requires a bit more workarounds than average.

This will also get a nice improvement when the Version parsing and
comparison PR gets merged! :D

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

launcher/meta/Version.cpp

@@ -99,6 +99,11 @@ QString Meta::Version::localFilename() const
     return m_uid + '/' + m_version + ".json";
 }
 
+::Version Meta::Version::toComparableVersion() const
+{
+    return { const_cast<Meta::Version*>(this)->descriptor() };
+}
+
 void Meta::Version::setType(const QString &type)
 {
     m_type = type;

launcher/meta/Version.h

@@ -16,6 +16,7 @@
 #pragma once
 
 #include "BaseVersion.h"
+#include "../Version.h"
 
 #include <QJsonObject>
 #include <QStringList>
@@ -85,6 +86,8 @@ public:
 
     QString localFilename() const override;
 
+    [[nodiscard]] ::Version toComparableVersion() const;
+
 public: // for usage by format parsers only
     void setType(const QString &type);
     void setTime(const qint64 time);