fix resource packs and add support for texture packs

Signed-off-by: Ryan Cao <70191398+ryanccn@users.noreply.github.com>

launcher/minecraft/mod/ResourcePack.h

@@ -42,6 +42,8 @@ class ResourcePack : public Resource {
     /** Thread-safe. */
     void setImage(QImage new_image);
 
+    bool valid() const override;
+
     [[nodiscard]] auto compare(Resource const& other, SortType type) const -> std::pair<int, bool> override;
     [[nodiscard]] bool applyFilter(QRegularExpression filter) const override;