Fix 404 when logged out - redirect to login

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Co-Authored-By: Claude <noreply@anthropic.com>

app.py

@@ -273,11 +273,11 @@ def index():
         except (json.JSONDecodeError, TypeError) as e:
             logger.warning(f"Invalid user settings JSON for user {current_user.id}: {e}")
             user_settings = {}
-        
+
         return render_template('dashboard.html', user_settings=user_settings)
     else:
-        # For non-authenticated users, serve static content
-        return send_from_directory('active_html/no_filter', 'index.html')
+        # Redirect non-authenticated users to login
+        return redirect(url_for('login'))
 
 
 @app.route('/feed/<filterset>')