feat: toggle diff explorer and show file change indicators

src/editor.rs

@@ -1279,8 +1279,13 @@ impl Editor {
     }
 
     fn handle_diff(&mut self, input: Input) {
-        // Escape and Tab always retain their modal close/back/focus semantics.
-        if !matches!(input, Input::Escape | Input::Char('\t') | Input::BackTab) {
+        // Modal controls take precedence over configured browsing bindings.
+        let toggle_files = input == Input::Ctrl('e')
+            && self
+                .diff
+                .as_ref()
+                .is_some_and(|diff| diff.phase == Phase::View);
+        if !toggle_files && !matches!(input, Input::Escape | Input::Char('\t') | Input::BackTab) {
             if self.handle_tree_binding(&input) {
                 return;
             }
@@ -2620,7 +2625,7 @@ impl Editor {
 
     fn handle_tree_binding(&mut self, input: &Input) -> bool {
         let picker = if let Some(diff) = &mut self.diff {
-            diff.files.as_mut()
+            diff.files.as_mut().filter(|_| diff.files_visible)
         } else {
             self.file_picker.as_mut()
         };