Add pipeline tag and library name

This PR adds the `pipeline_tag` and `library_name` to the model card metadata, improving discoverability and clarity. The `pipeline_tag` is set to `text-ranking` based on the model's description and usage examples. The `library_name` is set to `transformers` due to the provided code examples using the `transformers` library.

README.md

@@ -1,10 +1,13 @@
 ---
-license: cc-by-sa-4.0
-language:
-- en
 base_model:
 - meta-llama/Llama-3.1-8B
+language:
+- en
+license: cc-by-sa-4.0
+pipeline_tag: text-ranking
+library_name: transformers
 ---
+
 ## Model Summary
 ReasonIR-8B is the first retriever specifically trained for general reasoning tasks, achieving the state-of-the-art retrieval performance 
 on BRIGHT (reasoning-intensive retrieval).