Revert "settings: Remove auxiliary Content types where possible (#16744)" (#17768)

This breaks setting `{"scrollbar": {"show":"never"}}`
Release Notes:

- N/A

crates/collab_ui/src/chat_panel.rs

@@ -1108,7 +1108,7 @@ impl Panel for ChatPanel {
         settings::update_settings_file::<ChatPanelSettings>(
             self.fs.clone(),
             cx,
-            move |settings, _| settings.dock = position,
+            move |settings, _| settings.dock = Some(position),
         );
     }