Add task category and remove arXiv tag from metadata

README.md

@@ -1,15 +1,16 @@
 ---
-license: apache-2.0
 language:
 - en
+license: apache-2.0
 pretty_name: DolphinBench
+task_categories:
+- other
 tags:
 - benchmark
 - synthetic
 - agent-memory
 - tool-use
 - long-term-memory
-- arxiv:2609.24971
 configs:
 - config_name: messages
   default: true
@@ -73,4 +74,4 @@ All people, organizations, conversations, and app states in the dataset are synt
   journal={arXiv preprint arXiv:2609.24971},
   year={2026}
 }
-```
+```