Add basic ico support (#40822)

Closes https://github.com/zed-industries/zed/discussions/40763

<img width="867" height="1088" alt="Screenshot 2025-10-21 at 23 14 47"
src="https://github.com/user-attachments/assets/d691fb2a-afc6-4445-a335-054ef164e0d3"
/>

Also improves error handling on image open failure:

<img width="864" height="1083" alt="Screenshot 2025-10-21 at 23 14 30"
src="https://github.com/user-attachments/assets/d5388b61-995f-441b-b375-ad5136d1533b"
/>


Release Notes:

- Added basic ico support, improved unsupported image handling

crates/image_viewer/src/image_viewer.rs

@@ -1,6 +1,8 @@
 mod image_info;
 mod image_viewer_settings;
 
+use std::path::Path;
+
 use anyhow::Context as _;
 use editor::{EditorSettings, items::entry_git_aware_label_color};
 use file_icons::FileIcons;
@@ -18,6 +20,7 @@ use ui::prelude::*;
 use util::paths::PathExt;
 use workspace::{
     ItemId, ItemSettings, Pane, ToolbarItemLocation, Workspace, WorkspaceId, delete_unloaded_items,
+    invalid_item_view::InvalidItemView,
     item::{BreadcrumbText, Item, ProjectItem, SerializableItem, TabContentParams},
 };
 
@@ -389,6 +392,19 @@ impl ProjectItem for ImageView {
     {
         Self::new(item, project, window, cx)
     }
+
+    fn for_broken_project_item(
+        abs_path: &Path,
+        is_local: bool,
+        e: &anyhow::Error,
+        window: &mut Window,
+        cx: &mut App,
+    ) -> Option<InvalidItemView>
+    where
+        Self: Sized,
+    {
+        Some(InvalidItemView::new(abs_path, is_local, e, window, cx))
+    }
 }
 
 pub fn init(cx: &mut App) {