added a user system

sentence_api/assessment.py

@@ -28,6 +28,7 @@ class AssessmentService:
         audio_path: Path,
         language: Optional[str] = None,
         retained_audio_filename: Optional[str] = None,
+        user_id: str = "",
     ) -> AssessmentResult:
         if not self.transcriber.available:
             raise RuntimeError("MOSS transcription is not configured on this server.")
@@ -103,5 +104,6 @@ class AssessmentService:
                 sentence_index=sentence_index,
                 result=result.model_dump(mode="json"),
                 audio_filename=retained_audio_filename,
+                user_id=user_id,
             )
         return result