Keep all hunks expanded in proposed change editor (#18598)

Also, fix visual bug when pressing escape with a non-empty selection in
a deleted text block.

Release Notes:

- N/A

Co-authored-by: Antonio <antonio@zed.dev>

crates/editor/src/editor.rs

@@ -3059,7 +3059,7 @@ impl Editor {
     }
 
     pub fn cancel(&mut self, _: &Cancel, cx: &mut ViewContext<Self>) {
-        if self.clear_clicked_diff_hunks(cx) {
+        if self.clear_expanded_diff_hunks(cx) {
             cx.notify();
             return;
         }