fix: event classifier unwraps single-element list from model output

Model sometimes returns [{...}] instead of {...}. Now unwraps
single-element lists before parsing the event fields.

services/extractor/event_classifier.py

@@ -293,6 +293,12 @@ def _parse_classification_response(
     cleaned = _repair_json(cleaned)
     data = json.loads(cleaned)
 
+    # Model sometimes wraps the object in a list — unwrap it
+    if isinstance(data, list) and len(data) == 1 and isinstance(data[0], dict):
+        data = data[0]
+    if not isinstance(data, dict):
+        raise ValueError(f"Expected a JSON object, got {type(data).__name__}")
+
     confidence = data.get("confidence", 0.5)
     if isinstance(confidence, (int, float)):
         confidence = max(0.0, min(1.0, float(confidence)))