feat: add mod update dialog

This subclasses the Review mods dialog to make a "Update review" one.
Also, all the necessary components built until now are put together in a
coherent unity that checks and generates metadata on-the-fly and checks for
mod updates, while giving and receiving feedback to the user.

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

launcher/ui/dialogs/ModUpdateDialog.h

@@ -0,0 +1,61 @@
+#pragma once
+
+#include "BaseInstance.h"
+#include "ModDownloadTask.h"
+#include "ReviewMessageBox.h"
+
+#include "minecraft/mod/ModFolderModel.h"
+
+#include "modplatform/CheckUpdateTask.h"
+
+class Mod;
+class ModrinthCheckUpdate;
+class FlameCheckUpdate;
+
+class ModUpdateDialog final : public ReviewMessageBox {
+    Q_OBJECT
+   public:
+    explicit ModUpdateDialog(QWidget* parent,
+                             BaseInstance* instance,
+                             const std::shared_ptr<ModFolderModel>& mod_model,
+                             std::list<Mod>& search_for);
+
+    void checkCandidates();
+
+    void appendMod(const CheckUpdateTask::UpdatableMod& info);
+
+    const std::list<ModDownloadTask*> getTasks();
+    auto indexDir() const -> QDir { return m_mod_model->indexDir(); }
+
+    auto noUpdates() const -> bool { return m_no_updates; };
+    auto aborted() const -> bool { return m_aborted; };
+
+   private:
+    auto ensureMetadata() -> bool;
+
+   private slots:
+    void onMetadataEnsured(Mod&);
+    void onMetadataFailed(Mod&);
+
+   private:
+    QWidget* m_parent;
+
+    SequentialTask m_check_task;
+    ModrinthCheckUpdate* m_modrinth_check_task = nullptr;
+    FlameCheckUpdate* m_flame_check_task = nullptr;
+
+    const std::shared_ptr<ModFolderModel>& m_mod_model;
+
+    std::list<Mod>& m_candidates;
+    std::list<Mod> m_modrinth_to_update;
+    std::list<Mod> m_flame_to_update;
+
+    std::list<Mod> m_failed_metadata;
+    std::list<std::tuple<Mod, QString, QUrl>> m_failed_check_update;
+
+    QHash<QString, ModDownloadTask*> m_tasks;
+    BaseInstance* m_instance;
+
+    bool m_no_updates = false;
+    bool m_aborted = false;
+};