fix(gui): prevent dictionary size change during iteration

- Wrap discussions.items() with list() in takes_panel to prevent
  RuntimeError when dictionary changes during iteration
- This was causing crashes when switching discussions

src/gui_2.py

@@ -3024,7 +3024,7 @@ class App:
    imgui.table_setup_column("Entries", imgui.TableColumnFlags_.width_fixed, 80)
    imgui.table_setup_column("Actions", imgui.TableColumnFlags_.width_fixed, 150)
    imgui.table_headers_row()
-   for name, disc in discussions.items():
+   for name, disc in list(discussions.items()):
     imgui.table_next_row()
     imgui.table_set_column_index(0)
     is_active = name == self.active_discussion