Show file open error view instead of the modal (#36764)

Closes https://github.com/zed-industries/zed/issues/36672

Before:
either 
<img width="966" height="642" alt="image"
src="https://github.com/user-attachments/assets/7263ea3c-3d48-4f4d-be9e-16b24ca6f60b"
/>
(when opening from the project panel)

or

<img width="959" height="1019" alt="image"
src="https://github.com/user-attachments/assets/834041d4-f4d6-46db-b333-803169ec4803"
/>

(for the rest of the cases)

After:

<img width="2032" height="1167" alt="Screenshot 2025-08-22 at 19 34 10"
src="https://github.com/user-attachments/assets/1aa4530b-69f6-4c3a-8ea1-d4035dbb28da"
/>

(the unified error view)

Release Notes:

- Improved unsupported file opening in Zed

---------

Co-authored-by: Conrad Irwin <conrad.irwin@gmail.com>

crates/editor/src/editor_tests.rs

@@ -57,7 +57,9 @@ use util::{
 use workspace::{
     CloseActiveItem, CloseAllItems, CloseOtherItems, MoveItemToPaneInDirection, NavigationEntry,
     OpenOptions, ViewId,
+    invalid_buffer_view::InvalidBufferView,
     item::{FollowEvent, FollowableItem, Item, ItemHandle, SaveOptions},
+    register_project_item,
 };
 
 #[gpui::test]
@@ -24348,6 +24350,41 @@ async fn test_newline_replacement_in_single_line(cx: &mut TestAppContext) {
     });
 }
 
+#[gpui::test]
+async fn test_non_utf_8_opens(cx: &mut TestAppContext) {
+    init_test(cx, |_| {});
+
+    cx.update(|cx| {
+        register_project_item::<Editor>(cx);
+    });
+
+    let fs = FakeFs::new(cx.executor());
+    fs.insert_tree("/root1", json!({})).await;
+    fs.insert_file("/root1/one.pdf", vec![0xff, 0xfe, 0xfd])
+        .await;
+
+    let project = Project::test(fs, ["/root1".as_ref()], cx).await;
+    let (workspace, cx) =
+        cx.add_window_view(|window, cx| Workspace::test_new(project.clone(), window, cx));
+
+    let worktree_id = project.update(cx, |project, cx| {
+        project.worktrees(cx).next().unwrap().read(cx).id()
+    });
+
+    let handle = workspace
+        .update_in(cx, |workspace, window, cx| {
+            let project_path = (worktree_id, "one.pdf");
+            workspace.open_path(project_path, None, true, window, cx)
+        })
+        .await
+        .unwrap();
+
+    assert_eq!(
+        handle.to_any().entity_type(),
+        TypeId::of::<InvalidBufferView>()
+    );
+}
+
 #[track_caller]
 fn extract_color_inlays(editor: &Editor, cx: &App) -> Vec<Rgba> {
     editor

crates/editor/src/items.rs

@@ -42,6 +42,7 @@ use ui::{IconDecorationKind, prelude::*};
 use util::{ResultExt, TryFutureExt, paths::PathExt};
 use workspace::{
     CollaboratorId, ItemId, ItemNavHistory, ToolbarItemLocation, ViewId, Workspace, WorkspaceId,
+    invalid_buffer_view::InvalidBufferView,
     item::{FollowableItem, Item, ItemEvent, ProjectItem, SaveOptions},
     searchable::{Direction, SearchEvent, SearchableItem, SearchableItemHandle},
 };
@@ -1401,6 +1402,16 @@ impl ProjectItem for Editor {
 
         editor
     }
+
+    fn for_broken_project_item(
+        abs_path: PathBuf,
+        is_local: bool,
+        e: &anyhow::Error,
+        window: &mut Window,
+        cx: &mut App,
+    ) -> Option<InvalidBufferView> {
+        Some(InvalidBufferView::new(abs_path, is_local, e, window, cx))
+    }
 }
 
 fn clip_ranges<'a>(