remove dead code

backend/app/routers/recording_demo.py

@@ -26,6 +26,7 @@ from app.baked import pipeline as bp
 from app.services.synthetic_rtsp import SyntheticRtspManager
 from app.services.video_batch_cleanup import (
     purge_batch_artifacts,
+    purge_expired_pipeline_inputs,
     purge_expired_visualizations,
     purge_surgery_batch_tree,
     stage_visualization_pending,
@@ -75,6 +76,10 @@ def _background_finalize_visualization(
             runner.root_dir,
             ttl_hours=float(bp.VIDEO_BATCH_VIS_TTL_HOURS),
         )
+        purge_expired_pipeline_inputs(
+            runner.root_dir,
+            ttl_hours=float(bp.VIDEO_BATCH_PIPELINE_INPUT_TTL_HOURS),
+        )
 
 
 class OfflineBatchResponse(BaseModel):