add hints for changes

src/delta_barth/analysis/forecast.py

@@ -238,6 +238,7 @@ def _process_sales(
     too_few_month_points: bool = True
     forecast: pd.DataFrame | None = None
 
+    # change sliding window to monthly basis
     for start_year in range(current_year - 4, first_year - 1, -1):
         train = cast(
             pd.DataFrame,
@@ -274,9 +275,10 @@ def _process_sales(
                     best_score_mae = error
                     best_score_r2 = cast(float, r2_score(y_test, y_pred))
                     best_start_year = start_year
+                    # overwrite with pre-defined prognosis DF
                     forecast = test.copy()
                     forecast.loc[:, "vorhersage"] = y_pred
-
+    # remove
     if forecast is not None:
         forecast = forecast.drop(SALES_FEAT, axis=1).reset_index(drop=True)
     best_score_mae = best_score_mae if not math.isinf(best_score_mae) else None