Preserve read-only panning while canceling State edits

crates/oa-desktop/src/app/state_bend_tests.rs

@@ -305,7 +305,16 @@ fn state_bend_self_loop_add_move_remove_clear_preserves_project_and_source_histo
         vec![],
     );
     assert_eq!(app.project(), &baseline.decoded.project);
+    assert_source_model_agree(&app);
+    // Clear is a new source-preserving edit and may retain empty-list trivia.
+    // Exact original bytes are restored by history, not by reauthoring a value.
+    for _ in 0..3 {
+        assert!(app.document.can_undo());
+        send(&mut app, Message::Undo);
+    }
+    assert_eq!(app.project(), &baseline.decoded.project);
     assert_eq!(app.document.bundle(), &baseline.bundle);
+    assert!(!app.document.can_undo());
 }
 
 #[test]

crates/oa-desktop/src/behavior/state_canvas.rs

@@ -136,13 +136,16 @@ enum Hit {
 }
 
 impl State {
-    fn cancel_gesture(&mut self) {
+    fn cancel_edit(&mut self) {
         self.press = None;
         self.preview = None;
         self.attachment_preview = None;
         self.bend = None;
         self.bend_preview = None;
         self.attachment_viewport = None;
+    }
+    fn cancel_gesture(&mut self) {
+        self.cancel_edit();
         self.pan_from = None;
     }
     fn reset(&mut self) {
@@ -1178,7 +1181,9 @@ impl canvas::Program<Event> for StateCanvas<'_> {
             state.tool = Some(self.tool);
         }
         if !self.editable {
-            state.cancel_gesture();
+            // Pending edits block model changes, but read-only panning remains
+            // available and must survive successive pointer events.
+            state.cancel_edit();
             state.source = None;
         }
         if state