chore: switch default PII to LoRA with threshold 0.9

Update main config to use LoRA PII detector with optimized threshold,
consistent with e2e test profiles.

Author: yossiovadia

config/config.yaml

@@ -63,9 +63,9 @@ classifier:
     use_cpu: true
     category_mapping_path: "models/lora_intent_classifier_bert-base-uncased_model/category_mapping.json"
   pii_model:
-    model_id: "models/pii_classifier_modernbert-base_presidio_token_model"
-    use_modernbert: true
-    threshold: 0.7
+    model_id: "models/lora_pii_detector_bert-base-uncased_model"
+    use_modernbert: false
+    threshold: 0.9
     use_cpu: true
     pii_mapping_path: "models/pii_classifier_modernbert-base_presidio_token_model/pii_type_mapping.json"