refactor: move modrinth modpack import to separate file

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

launcher/modplatform/modrinth/ModrinthInstanceCreationTask.h

@@ -0,0 +1,39 @@
+#pragma once
+
+#include "InstanceCreationTask.h"
+
+#include "modplatform/modrinth/ModrinthPackManifest.h"
+
+#include "net/NetJob.h"
+
+class ModrinthCreationTask final : public InstanceCreationTask {
+    Q_OBJECT
+
+   public:
+    ModrinthCreationTask(QString staging_path, SettingsObjectPtr global_settings, QWidget* parent, QString source_url = {})
+        : InstanceCreationTask(), m_parent(parent)
+    {
+        setStagingPath(staging_path);
+        setParentSettings(global_settings);
+    }
+
+    bool abort() override;
+    bool canAbort() const override { return true; }
+
+    bool updateInstance() override;
+    bool createInstance() override;
+
+   private:
+    bool parseManifest();
+    QString getManagedPackID() const;
+
+   private:
+    QWidget* m_parent = nullptr;
+
+    QString minecraftVersion, fabricVersion, quiltVersion, forgeVersion;
+    QString m_managed_id, m_managed_version_id, m_managed_name;
+    QString m_source_url;
+
+    std::vector<Modrinth::File> m_files;
+    NetJob::Ptr m_files_job;
+};