Settings refactor (#38367)

Co-Authored-By: Ben K <ben@zed.dev>
Co-Authored-By: Anthony <anthony@zed.dev>
Co-Authored-By: Mikayla <mikayla@zed.dev>

Release Notes:

- settings: Major internal changes to settings. The primary user-facing
effect is that some settings which did not make sense in project
settings files are no-longer read from there. (For example the inline
blame settings)

---------

Co-authored-by: Ben Kunkle <ben@zed.dev>
Co-authored-by: Mikayla Maki <mikayla.c.maki@gmail.com>
Co-authored-by: Anthony <anthony@zed.dev>

crates/ui/src/components/scrollbar.rs

@@ -45,6 +45,17 @@ pub mod scrollbars {
         Never,
     }
 
+    impl From<settings::ShowScrollbar> for ShowScrollbar {
+        fn from(value: settings::ShowScrollbar) -> Self {
+            match value {
+                settings::ShowScrollbar::Auto => ShowScrollbar::Auto,
+                settings::ShowScrollbar::System => ShowScrollbar::System,
+                settings::ShowScrollbar::Always => ShowScrollbar::Always,
+                settings::ShowScrollbar::Never => ShowScrollbar::Never,
+            }
+        }
+    }
+
     impl ShowScrollbar {
         pub(super) fn show(&self) -> bool {
             *self != Self::Never