refactor: Make Args less of a singleton (#5041)

This means it's no longer a singleton, and its lifetime is bound to our application.
This felt like a good small experiment to see how its changes would look
if we did this.
As a shortcut, `getApp` that is already a mega singleton keeps a
reference to Args, this means places that are a bit more difficult to
inject into call `getApp()->getArgs()` just like other things are
accessed.

src/singletons/CrashHandler.hpp

@@ -12,6 +12,8 @@
 
 namespace chatterino {
 
+class Args;
+
 class CrashHandler : public Singleton
 {
 public:
@@ -30,7 +32,7 @@ private:
 };
 
 #ifdef CHATTERINO_WITH_CRASHPAD
-std::unique_ptr<crashpad::CrashpadClient> installCrashHandler();
+std::unique_ptr<crashpad::CrashpadClient> installCrashHandler(const Args &args);
 #endif
 
 }  // namespace chatterino