chore: drop unused code

dzgui/model/proxy_model.py

@@ -259,10 +259,6 @@ class ProxyModelManager:
     def set_cache(self, filters: tuple[str], filtered_rows: list[tuple]) -> None:
         self.filter_cache[filters] = filtered_rows
 
-    # @deprecated("Currently unused")
-    # def convert_model_to_list(self, model: "FastInsertListStore") -> list:
-    #    return [[el for el in row] for row in model]
-
     def set_filtered(self, rows: list | None) -> None:
         if rows is None:
             self.filtered = []