Fix syntax errors

app.py

@@ -90,8 +90,8 @@ def format_pipeline_results(results: Dict[str, Any]) -> str:
 
     # Header
     html_parts.append(
-        f"<h3 style='color: #333; margin-bottom: 20px;'>Found {
-            len(constructions)} construction(s):</h3>")
+        "<h3 style='color: #333; margin-bottom: 20px;'>Found {} construction(s):</h3>".format(
+            len(constructions)))
 
     # Process each construction
     for i, construction in enumerate(constructions, 1):