Show model names only for frontier points in Evolution chart

- Track frontier_rows when computing Pareto frontier
- Only add model name labels for points on the frontier
- Matches behavior of Cost/Performance and Accuracy by Size charts

visualizations.py

@@ -214,6 +214,8 @@ def create_evolution_over_time_chart(df: pd.DataFrame) -> go.Figure:
     fig = go.Figure()
     
     # Add Pareto frontier line (monotonically increasing best score over time)
+    # Also track which rows are on the frontier for labeling
+    frontier_rows = []
     if len(plot_df) > 1:
         # Compute Pareto frontier: only include points that set a new best score
         frontier_dates = []
@@ -228,6 +230,7 @@ def create_evolution_over_time_chart(df: pd.DataFrame) -> go.Figure:
                 # This point is on the Pareto frontier
                 frontier_dates.append(current_date)
                 frontier_scores.append(current_score)
+                frontier_rows.append(row)
                 max_score_so_far = current_score
         
         if frontier_dates:
@@ -281,7 +284,6 @@ def create_evolution_over_time_chart(df: pd.DataFrame) -> go.Figure:
     
     # Add company logo images for each data point using data coordinates
     layout_images = []
-    labels_data = []
     
     for _, row in plot_df.iterrows():
         model_name = row.get(model_col, '')
@@ -311,24 +313,28 @@ def create_evolution_over_time_chart(df: pd.DataFrame) -> go.Figure:
                         yanchor="middle",
                         layer="above"
                     ))
-                    
-                    # Store label data for annotation
-                    labels_data.append({
-                        'x': x_val,
-                        'y': y_val,
-                        'label': model_name
-                    })
             except Exception:
                 pass
     
-    # Add model name labels above each point
-    for item in labels_data:
+    # Add model name labels only for frontier points
+    for row in frontier_rows:
+        model_name = row.get(model_col, '')
+        x_val = row['release_date']
+        y_val = row[score_col]
+        
+        # Clean model name for label
+        if isinstance(model_name, list):
+            model_name = model_name[0] if model_name else ''
+        model_name = str(model_name).split('/')[-1]
+        if len(model_name) > 25:
+            model_name = model_name[:22] + '...'
+        
         fig.add_annotation(
-            x=item['x'],
-            y=item['y'],
+            x=x_val,
+            y=y_val,
             xref="x",
             yref="y",
-            text=item['label'],
+            text=model_name,
             showarrow=False,
             yshift=20,
             font=STANDARD_FONT,