[irc] Partially fix IRC colors (#1594)

Doesn't fix #1379 but it is a big step forward.

Needs some "real life" testing, but should be good.

src/providers/irc/IrcMessageBuilder.hpp

@@ -0,0 +1,41 @@
+#pragma once
+
+#include "common/Aliases.hpp"
+#include "common/Outcome.hpp"
+#include "messages/SharedMessageBuilder.hpp"
+#include "providers/twitch/TwitchBadge.hpp"
+
+#include <IrcMessage>
+#include <QString>
+#include <QVariant>
+
+namespace chatterino {
+
+struct Emote;
+using EmotePtr = std::shared_ptr<const Emote>;
+
+class Channel;
+class TwitchChannel;
+
+class IrcMessageBuilder : public SharedMessageBuilder
+{
+public:
+    IrcMessageBuilder() = delete;
+
+    explicit IrcMessageBuilder(Channel *_channel,
+                               const Communi::IrcPrivateMessage *_ircMessage,
+                               const MessageParseArgs &_args);
+    explicit IrcMessageBuilder(Channel *_channel,
+                               const Communi::IrcMessage *_ircMessage,
+                               const MessageParseArgs &_args, QString content,
+                               bool isAction);
+
+    MessagePtr build() override;
+
+private:
+    void appendUsername();
+
+    void addWords(const QStringList &words);
+};
+
+}  // namespace chatterino