project_search: Add button to collapse/expand all excerpts (#41654)

<img width="500" height="834" alt="Screenshot 2025-11-03 at 12  59@2x"
src="https://github.com/user-attachments/assets/15c5e1fc-2291-41b4-9eec-a8cfa5a446c7"
/>

Releases Note:

- Added a button that allows to expand/collapse all project search
excerpts at once.

---------

Co-authored-by: Danilo Leal <daniloleal09@gmail.com>

crates/workspace/src/item.rs

@@ -296,6 +296,15 @@ pub trait Item: Focusable + EventEmitter<Self::Event> + Render + Sized {
         None
     }
 
+    /// Returns optional elements to render to the left of the breadcrumb.
+    fn breadcrumb_prefix(
+        &self,
+        _window: &mut Window,
+        _cx: &mut Context<Self>,
+    ) -> Option<gpui::AnyElement> {
+        None
+    }
+
     fn added_to_workspace(
         &mut self,
         _workspace: &mut Workspace,
@@ -479,6 +488,7 @@ pub trait ItemHandle: 'static + Send {
     fn to_searchable_item_handle(&self, cx: &App) -> Option<Box<dyn SearchableItemHandle>>;
     fn breadcrumb_location(&self, cx: &App) -> ToolbarItemLocation;
     fn breadcrumbs(&self, theme: &Theme, cx: &App) -> Option<Vec<BreadcrumbText>>;
+    fn breadcrumb_prefix(&self, window: &mut Window, cx: &mut App) -> Option<gpui::AnyElement>;
     fn show_toolbar(&self, cx: &App) -> bool;
     fn pixel_position_of_cursor(&self, cx: &App) -> Option<Point<Pixels>>;
     fn downgrade_item(&self) -> Box<dyn WeakItemHandle>;
@@ -979,6 +989,10 @@ impl<T: Item> ItemHandle for Entity<T> {
         self.read(cx).breadcrumbs(theme, cx)
     }
 
+    fn breadcrumb_prefix(&self, window: &mut Window, cx: &mut App) -> Option<gpui::AnyElement> {
+        self.update(cx, |item, cx| item.breadcrumb_prefix(window, cx))
+    }
+
     fn show_toolbar(&self, cx: &App) -> bool {
         self.read(cx).show_toolbar()
     }