Implement rendering of images with data urls in markdown (#30322)

Fixes #28266

![Screenshot 2025-05-08 at 5 08
21 PM](https://github.com/user-attachments/assets/774d2dde-3f2d-466c-8eb1-c67badbd89e4)

Release Notes:

- Added support for rendering images with data URLs in markdown. This
can show up in hover documentation provided by language servers.

Co-authored-by: Mikayla Maki <mikayla.c.maki@gmail.com>

crates/gpui/src/window.rs

@@ -2100,14 +2100,14 @@ impl Window {
         let (task, is_first) = cx.fetch_asset::<A>(source);
         task.clone().now_or_never().or_else(|| {
             if is_first {
-                let entity = self.current_view();
+                let entity_id = self.current_view();
                 self.spawn(cx, {
                     let task = task.clone();
                     async move |cx| {
                         task.await;
 
                         cx.on_next_frame(move |_, cx| {
-                            cx.notify(entity);
+                            cx.notify(entity_id);
                         });
                     }
                 })