feat: PG-очередь — classify_status='processing' для crash recovery

deploy/db/documents.py

@@ -70,13 +70,21 @@ def list_pending(batch_id):
 
 
 def reset_classify_status(batch_id):
-    """Сбросить classify_status на 'pending' для всех документов батча."""
+    """Сбросить classify_status на 'pending' для всех документов батча (включая 'processing' — crash recovery)."""
     return execute(
         "UPDATE documents SET classify_status='pending', error_message=NULL WHERE batch_id=%s",
         (batch_id,),
     )
 
 
+def set_classify_processing(doc_id):
+    """Mark document as being processed (for crash recovery)."""
+    return execute(
+        "UPDATE documents SET classify_status='processing' WHERE id=%s",
+        (doc_id,),
+    )
+
+
 def list_by_batch(batch_id):
     """All documents in a batch with classification fields."""
     return query(