Fix/qa defects df002 df011 (#9)

## Summary

What changed and why?

## Change Type

- [ ] Cowork feature
- [ ] Bug fix
- [ ] Core AI contribution
- [ ] Test / hardening
- [ ] Performance
- [ ] Documentation

## Related Work

Cowork Task:

Core Repo: http://34.143.229.138/gitea-admin/fsg-ai-core-assets

Core AI Issue:

Core Task:

Related PR:

## Scope

What is intentionally included?

What is intentionally NOT included?

## Validation

- [ ] Unit tests
- [ ] Integration tests
- [ ] Manual verification
- [ ] Regression check

Commands / evidence:

## Security Impact

Permission / credential / network / customer data impact:

## Compatibility

- [ ] No breaking change
- [ ] Breaking change documented

## Reviewer Notes

Anything Cowork reviewers should pay attention to.

---------

Co-authored-by: thanhnv <thanhnv.ip@gmail.com>
Co-authored-by: Vu Dam Tuan <vudt15@fpt.com>
Reviewed-on: #9

presentation/co4e/canvas_items.py

@@ -199,6 +199,14 @@ class _NodeItem(QGraphicsObject):
             e.accept()
             return
         super().mousePressEvent(e)
+        if self.isSelected():
+            # itemChange() only emits node_selected when the SELECTION STATE
+            # actually flips (ItemSelectedHasChanged) — clicking a node that
+            # was already selected (e.g. left selected when a run started)
+            # never re-fires it, so the property panel silently kept showing
+            # stale data and looked "locked" while the node ran. Emit
+            # explicitly on every click so the panel always reloads.
+            self.canvas.node_selected.emit(self.node.id)
 
     def mouseMoveEvent(self, e):
         """Rê chuột trong lúc kéo nối: vẽ lại đường nét đứt theo con trỏ."""