Corrected the way we parse comma-separated "list tags" in PRIVMSGs (#3771)

tl;dr: we now split by slash only its first occurrence instead of every occurrence.

src/messages/SharedMessageBuilder.hpp

@@ -3,6 +3,7 @@
 #include "common/Aliases.hpp"
 #include "common/Outcome.hpp"
 #include "messages/MessageColor.hpp"
+#include "providers/twitch/TwitchBadge.hpp"
 
 #include <IrcMessage>
 #include <QColor>
@@ -32,6 +33,11 @@ public:
     virtual void triggerHighlights();
     virtual MessagePtr build() = 0;
 
+    static std::pair<QString, QString> slashKeyValue(const QString &kvStr);
+
+    // Parses "badges" tag which contains a comma separated list of key-value elements
+    static std::vector<Badge> parseBadgeTag(const QVariantMap &tags);
+
 protected:
     virtual void parse();