Don't autosave unmodified buffers (#32626)

Closes https://github.com/zed-industries/zed/issues/12091

Proper redo of https://github.com/zed-industries/zed/pull/32603

Release Notes:

- Fixed formatting effects not triggered when saving unmodified
singleton buffers

---------

Co-authored-by: Max Brunsfeld <maxbrunsfeld@gmail.com>
Co-authored-by: Cole Miller <m@cole-miller.net>

crates/git_ui/src/project_diff.rs

@@ -37,7 +37,7 @@ use util::ResultExt as _;
 use workspace::{
     CloseActiveItem, ItemNavHistory, SerializableItem, ToolbarItemEvent, ToolbarItemLocation,
     ToolbarItemView, Workspace,
-    item::{BreadcrumbText, Item, ItemEvent, ItemHandle, TabContentParams},
+    item::{BreadcrumbText, Item, ItemEvent, ItemHandle, SaveOptions, TabContentParams},
     searchable::SearchableItemHandle,
 };
 
@@ -632,12 +632,12 @@ impl Item for ProjectDiff {
 
     fn save(
         &mut self,
-        format: bool,
+        options: SaveOptions,
         project: Entity<Project>,
         window: &mut Window,
         cx: &mut Context<Self>,
     ) -> Task<Result<()>> {
-        self.editor.save(format, project, window, cx)
+        self.editor.save(options, project, window, cx)
     }
 
     fn save_as(
@@ -1565,7 +1565,15 @@ mod tests {
 
         cx.update_window_entity(&buffer_editor, |buffer_editor, window, cx| {
             buffer_editor.set_text("different\n", window, cx);
-            buffer_editor.save(false, project.clone(), window, cx)
+            buffer_editor.save(
+                SaveOptions {
+                    format: false,
+                    autosave: false,
+                },
+                project.clone(),
+                window,
+                cx,
+            )
         })
         .await
         .unwrap();