feat: include more data when copying messages as JSON (#5600)

src/messages/ImageSet.hpp

@@ -4,6 +4,8 @@
 
 #include <memory>
 
+class QJsonObject;
+
 namespace chatterino {
 
 class Image;
@@ -34,6 +36,8 @@ public:
     bool operator==(const ImageSet &other) const;
     bool operator!=(const ImageSet &other) const;
 
+    QJsonObject toJson() const;
+
 private:
     ImagePtr imageX1_;
     ImagePtr imageX2_;