feat: add --safe-mode command line option (#4985)

This ensures the settings button isn't hidden, and disables plugins from being loaded to make sure the user can always recover from messing things up

src/widgets/Window.cpp

@@ -1,6 +1,7 @@
 #include "widgets/Window.hpp"
 
 #include "Application.hpp"
+#include "common/Args.hpp"
 #include "common/Credentials.hpp"
 #include "common/Modes.hpp"
 #include "common/QLogging.hpp"
@@ -736,6 +737,11 @@ void Window::onAccountSelected()
     }
 #endif
 
+    if (getArgs().safeMode)
+    {
+        windowTitle += " (safe mode)";
+    }
+
     this->setWindowTitle(windowTitle);
 
     // update user