Remove Unnecessary Includes in Headers (#4275)

* refactor: remove unnecessary includes in headers

* fix: formatting

* chore: changelog

* fix: scrollbar

* fix: suggestions and old appbase remains

* fix: suggestion

* fix: missing Qt forward declarations

* fix: another qt include

* fix: includes for precompiled-headers=off

* Add missing `<memory>` includes

* Add missing `#pragma once`

* Fix tests

Co-authored-by: Rasmus Karlsson <rasmus.karlsson@pajlada.com>

src/singletons/Logging.hpp

@@ -1,14 +1,18 @@
 #pragma once
 
 #include "common/Singleton.hpp"
-#include "messages/Message.hpp"
-#include "singletons/helper/LoggingChannel.hpp"
 
+#include <QString>
+
+#include <map>
 #include <memory>
 
 namespace chatterino {
 
 class Paths;
+struct Message;
+using MessagePtr = std::shared_ptr<const Message>;
+class LoggingChannel;
 
 class Logging : public Singleton
 {