feat: Enhance context generation and report generation services with improved data handling and structure

app/services/graph_generator.py

@@ -8,6 +8,9 @@ Based on the analysis notebooks in services_dfdf/.
 import base64
 from pathlib import Path
 
+import matplotlib
+
+matplotlib.use("Agg")  # Use non-interactive backend
 import matplotlib.pyplot as plt
 import matplotlib.transforms as mtransforms
 import numpy as np