Maintain selection on file/dir deletion in project panel (#20577)

Closes #20444

- Focus on next file/dir on deletion.
- Focus on prev file/dir in case where it's last item in worktree.
- Tested when multiple files/dirs are being deleted.

Release Notes:

- Maintain selection on file/dir deletion in project panel.

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Co-authored-by: Kirill Bulatov <kirill@zed.dev>

crates/workspace/src/pane.rs

@@ -48,7 +48,7 @@ use ui::{v_flex, ContextMenu};
 use util::{debug_panic, maybe, truncate_and_remove_front, ResultExt};
 
 /// A selected entry in e.g. project panel.
-#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord)]
+#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct SelectedEntry {
     pub worktree_id: WorktreeId,
     pub entry_id: ProjectEntryId,